Mark Rouw BIG Tree: Updated Report Jan-Jun 2023

Iowa Big Tree Report for January Through June of 2023

Submitted By Mark Rouw, Iowa Big Tree Field Representative

Although several different species of trees were measured, I would describe the first half of 2023 as the half- year of the cottonwoods. I don’t remember ever measuring so many cottonwoods over such a short time!

January 2nd

For many years I have admired a sycamore that grows in a yard on the west side of Des Moines. It doesn’t have a particularly large trunk, so it was never a priority tree. This tree is very beautiful, and I have always been curious to know the height which I suspected may reach or surpass 100’. The young lady who owned the property loves trees and later, I saw her at the Shade Tree Short Course! I determined the sycamore to have these dimensions:

Circ. 14.71’, height 105’, spread 104.79’, index 307.698, rank # 23

January 3rd

Scott Carlson joined me to measure one of the bigger cottonwoods in Des Moines. Here are the dimensions of this cottonwood growing on the west side of town:

Circ. 21.875’, height 99.33’, spread 109.165’, index 389.121, rank # 12

January 10th

Today I went to Laurel Hill Cemetery in Des Moines to measure a sycamore that I first measured in 2010. It is a beautiful tree and I enjoy visiting it nearly every year. Here are the updated dimensions of the sycamore:

Circ. 16.21’, height 98.17’, spread 106.29, index 319.243, rank # 16

Later that day, Scott Carlson and I met Heath Ellis to update the dimensions of the second largest sycamore in Des Moines. It had been several years since I updated the measurements of this tree, so I was anxious to get the stats up to date. We found the sycamore to have these dimensions:

Circ. 16.5’, height 103.5’, spread 105.085’, index 321.771, rank # 15

January 11th

I went to Ames to check out a honey locust that had been nominated several months earlier. Although it would not be close to record size, it is always good to see an owner like this one who is excited about their tree! I determined the locust to have these dimensions:

Circ. 13.375’, height 73.5’, spread 81.5’, index 250.375, rank # 12

While in Ames, I was anxious to see a Katsura at Iowa State University that was on the spreadsheet but somehow, I had never seen the tree. It turned out to be a beautiful tree with a single trunk. Here are the dimensions of the Katsura:

Circ. 7.67’, height 55.67’, spread 58.625’, index 162.326, rank # 1

January 17th

Scott joined me to update the measurements of perhaps the largest pin oak remaining in Iowa. This tree has a split and I was told the tree would be coming down, but to my surprise, a compromise was agreed upon which gave the tree a stay of execution! The ends of some of the branches connected to the trunk on the weaker side of the split were cut back. This measure may buy the tree some time but now it is left with many stubs which will lead to future problems. The spread was measured prior to the branches being cut. We determined this pin oak to have the following dimensions:

Circ. 17.92’, height 85.42’, spread 100.5’, index 325.545, rank # 1

Not far from the previous tree on the south side of Des Moines stands a butternut that I have been monitoring for several years. Scott and I found the tree to have these dimensions:

Circ. 11.92’, height 61.83’, spread 65.045’, index 221.091, rank # 1

Although this is a good- sized butternut, the former champion from Lisbon had 270 points!

February 21st

I met Shane Hammond in Carlisle, and he showed me an old property that had several Osage orange trees. Similar to silver maples and white mulberries, Osage oranges are notorious for having multiple trunks. There are several other Osage oranges in Iowa that have larger trunks, but they all appear to have two or more trunks. There is some question in my mind concerning the trunk of the largest Osage orange in Carlisle but the second largest one appears to be a definite single trunk. Here are the dimensions of the two Carlisle Osage oranges:

Circ. 11.92’, height 58.33’, spread 66.125’, index 216.861, rank # 1

Circ. 10.79’, height 58.58’, spread 68’, index 205.16, rank # 2

From Carlisle we went to the Indianola Cemetery to update the measurements of one the largest white pines and the co-champion red cedar. The white pine is in poor shape. It hast lost several big limbs which has reduced the spread considerably. Below the point where a couple of the big limbs were lost,  a wide vertical strip of the trunk is showing considerable decay. This tree may not be around much longer. The wind was blowing, and the tree was making some creaking sounds that a tree should not be making! Here are the dimensions of the white pine and red cedar:

White pine- Circ. 16.25’ (1979 circ. 11’), height 82.08’, spread 59.5’, index 291.196, rank # 3

Red cedar- Circ. 10.75’, height 64.7’, spread 39’, index 200.92, rank # 2 (co-champ)

March 20th

I take pride in knowing I have walked almost every block of every street in Des Moines. With this in mind, you can understand my astonishment when I found a surprise on the south side of Des Moines. After an appointment on the far south side of Des Moines, I decided to drive some of the side streets to see trees I have not seen for a long time. Not only did I see trees I had not seen in some time, I also saw a tree I had never seen before. Although not a champion, the tree I came across was distinctive and I would have remembered seeing this one. The tree I found was an American elm with a beautiful, dense crown and an immense spread! Shane Hammond and I found the elm to have these dimensions:

Circ. 14.08’, height 67.75’, spread 118.915 (max. spread 125.5’) index 266.479, rank # 12

March 27th

I headed to Burlington with a stop in Ottumwa along the way. It took several attempts, but I finally received permission to measure a large Kentucky coffeetree in an old section of Ottumwa. The coffeetree did not disappoint with the following dimensions:

Circ. 10.54’, height 81.08’, spread 63.25’, index 221.705, rank # 4

Next, I headed to a property where I noticed a large ponderosa pine on a previous visit. Luckily the owner was home, and they were cooperative. This tree did not turn out to be quite as big as I had hoped, but it was still a very respectable ponderosa pine. Here are the dimensions of the tree:

Circ. 7.67’, height 65.33’, spread 39.25’, index 157.33, rank # 9

Next, I checked on a couple of potentially big black locusts that I had noticed earlier. I didn’t have time to measure both, so I concentrated on what appeared to be the largest one. Boy, did this turn out to be a pleasant surprise. Not only did it have a big trunk, but it was very tall as well! I determined black locust to have the following dimensions:

Circ. 10.82’, height 97.5’, spread 40.75, index 236.688, rank # 1

It was getting late in the day, so I decided to forego additional tree measuring and continued toward my destination, Burlington.

March 28th

In the morning I met several people including Patrick Moore who is the Burlington City Forester and Andy Dahl, who is the arborist for the University of Iowa. As much time as I have spent covering Burlington, I was a little surprised when Patrick Moore mentioned a large chinkapin oak that I had not yet found. Thanks to Patrick for finding and sharing the location of this exceptional tree! Here are the dimensions of the chinkapin oak:

Circ. 12.42’, height 80.33’, spread 93.625, index 252.576, rank # 2

This tree does have some issues including a section of the trunk without bark which has begun to decay. This tree grows on a bank close to a house and much of the soil in the yard has been altered so it is very difficult to determine where the oak germinated. My estimation of where 4 ½’above the ground may be off somewhat but I did the best I could.

After measuring the chinkapin oak, Andy and I went to Aspen Grove Cemetery in Burlington, and we met with Michael Bloomer the Administrator of Aspen Grove. We proceeded to tour the cemetery primarily to show Michael where the most significant trees were located. I wanted to measure the height of my favorite baldcypress which has been mentioned in at least one previous report. My most recent measurement of the height revealed a height that was less than the previous measurement. After determining the height this time, I realized I had missed the highest point on my previous attempt. This time I hit the highest twig and then it all made sense! Here are the dimensions of the biggest baldcypress in Aspen Grove:

Circ. 12.5’, height 84.75’, spread 66.25’, index 250.893, rank #2 (co-champion)

Unfortunately, we noticed this tree has a large constricting root which may be too large to remove. I wonder if a narrow strip of bark were to be removed along the junction of where the trunk meets the constricting root if the two could possibley become grafted which might be a better outcome in the long run. Perhaps some knowledgeable arborists could examine the tree and come to a consensus as to whether it would be better to intervene, or take no action. Not only is this tree the number two baldcypress in Iowa, but it is the tallest, and, in my opinion, the most impressive!

Not far from the # 2 baldcypress grows another one that is very respectable. I had noticed this tree many years ago, but I had never found time to measure it until now: Here are the dimensions of this baldcypress:

Circ. 10’, height 82’, spread 52, index 215, rank # 7

One of the trees we looked at in Aspen Grove was the big Norway spruce that I described in my last report. This spruce has a circumference of 14.17’ and the height measures 108.33’. If Andy and Michael were half as impressed with this tree as I was, then I know it left quite an impression.

After leaving Aspen Grove, Andy and I went to the Perkins Park neighborhood to visit the largest baldcypress in Iowa. Like the tall baldcypress in Aspen Grove Cemetery this one appears to have a constricting root as well. Perhaps a certain arborist will try to help this situation. Here are the updated dimensions of this champion:

Circ. 14’, height 72.33’, spread 69.5’, index 257.705, rank # 1

There are two baldcypress on this property, and although one is considerably smaller than the champion, it is still one of the biggest in Iowa. Here are the dimensions of the smaller baldcypress:

Circ. 10.75’, height 72’, spread 56.5’, index 215.125, rank # 6

April 10th

I met with Earl Gerveler who lives near Franklin in Lee County. Earl has a very impressive sycamore growing on his property. It ranks as the 13th largest, and it has a maximum spread of 143.5’! There were two big sycamores, but both trees stood near Sugar Creek, and the stream had undercut the larger tree which caused it to topple. On this day, we were going to check on another sycamore that stands on a nearby property. I had spotted this tree a few years earlier, but I struck out with my first attempt to contact the owner. Interestingly, Jeff Carstens had this tree in his sites as a tree from which to collect seed. He had visited the site prior to me, and based on his measurements, I decided the tree was worth measuring. I determined the tree to have the following dimensions:

Circ. 14.82’, height 106.67’, spread 103.58’, 125.92’=114.70’, index 312.346, rank # 21

Because of the nearly white bark, sycamores are probably the easiest trees to identify using satellite imagery. I’m sure I looked at the next tree using that technique, but looking from above; this tree appears to be two sycamores or a tree with a double trunk. This sycamore occurred in an area Jeff Carstens had picked for seed collection. Jeff sent me photos of this tree and although the trunk divides fairly close to the ground it appears to have a single trunk. Please pay attention to the spread of this tree. It has the greatest spread of any known Iowa tree, surpassing the spread of the aforementioned Gerveler sycamore! I determined this sycamore to have the following dimensions:

Circ. 20.21’ (@ approx. 2’ above the ground), height 109.5’, spread 155’, 142.5’=148.75’, index 389.188, rank # 3

April 11th

I checked a few trees in Burlington, and I measured one red maple that was good sized but not exceptional. Now it was time to go to Geode State Park where I hoped to meet with a reporter for the Burlington newspaper. Unfortunately, there was some miscommunication, and we were unable to meet. I was in Geode State Park primarily to update measurements of the state champion sycamore. The trunk of this tree is atypical and there is no point on the trunk where I feel good about measuring the circumference. On the north side of the tree there is a big cavity which may have been where another trunk stood at one time. This gives the trunk an exaggerated circumference at 4 ½’. There is also a smaller cavity next to the large one where a limb used to grow straight up. This anomaly also inflates the circumference for some distance above 4 ½’. My best solution to this problem is to measure above the smaller cavity where the circumference is less distorted and measure the trunk at 4 ½’ and average the two measurements. The circumference at 4 ½’ is 24.54’ and the measurement above the smaller cavity, which is six or seven feet above the ground results in a measurement of 22.58’ for an average of 23.54’ Because of some storm damage the height and spread are somewhat less than my previous measurements but the trunk continues to grow so the total points remain about the same. Here are the most current measurements for the state champion sycamore:

Circ. 23.54”, height 103.17’, spread 73.5’, index 404.045, rank # 1

Also in Geode State Park stands a very tall cottonwood which I had measured a few years prior. The circumference and spread dimensions are unremarkable, but the height is up there with the tallest in Iowa.  I was anxious to see if this tree might now be the tallest cottonwood. Shooting to the highest twigs with my rangefinder, I found the greatest height to be 124.25’. I measured one in Waubonsie State Park that reached a height of 123.67’ but the 124’ barrier had never been broken here in Iowa!

After leaving Geode, I headed back to Burlington. There would be time only to measure one more tree for the day, so I decided to see if the owner of a large persimmon was at home.  The owner was home, and I received permission to measure the tree. This persimmon turned out to be four points bigger than the former champion! It should be noted that the former champion in Des Moines was damaged by the 2020 derecho and the height was reduced considerably. Here are the dimensions of the Burlington persimmon:

Circ. 7.58’, height 57.83’, spread 48.75’, index 161.0175, rank # 1

April 12th

Unlike most days on my tree trips, I was able to get started very early in the morning. I already had permission to measure a large tulip tree located on S. Starr Ave. in Burlington. I was very familiar with this location since I had measured two trees here in the past.  One of these trees was a tulip tree which became a state champion in 1986. The other tree was a cucumbertree that had a circumference of 11’ and an incredible height of 98’. Both the tulip tree and the cucumbertree were destroyed by storms. In 1986 the tulip tree I was measuring today was much smaller than the former champion on the same property. I remember the tree from back then, and I was thinking this would be a good tree someday. Well, today was the “someday” I envisioned many years ago. It wasn’t until after it was measured, and the points were totaled that I realized this tulip tree was now bigger than the former champion that stood on the same property! I found the tulip tree to have the following dimensions:

Circ. 15.42’, height 105.75’, spread 79.5’, index 310.625, rank # 5

On the same property is a nice hemlock that had a height of 75.5’ which is very respectable, but it ranked at only # 17 out of 20 measured hemlocks.

I received permission from the owner of the adjacent property to measure a basswood that stood near the property line. It was difficult to determine whether this tree had a single trunk. Giving it the benefit of the doubt, I found it to have these dimensions:

Circ. 15.42’, height 74.5’, spread 74.585’, index 278.066, rank # 3

Just a few blocks away on S. Starr Ave. stands another impressive tulip tree. The owner, Sabrina, was very receptive to the idea of me measuring her tree. She was interested in learning the dimensions of the tree and she hoped it would be number one. I determined the tree to have the following dimensions:

Circ. 15.08’, height 105.25’, spread 80.25’, index # 8

After several attempts to get permission to measure a big cottonwood in Burlington, I finally received permission. Upon close inspection, I was disappointed because the tree has a limb that probably disqualifies the tree as having a single trunk.

Circ. (including the merged limb 21.83’) height 109.5’, spread not measured

After many years since first seeing the tree, I finally was able to measure a respectable Burlington white oak. Here are the white oak’s dimensions:

Circ. 13.5”, height 66.08’, spread 99.5’, index 253, rank # 15

April 17th

Three weeks earlier, while visiting Ottumwa, I measured what would become the new state champion black locust. I was back with Shane Hammond to measure a second black locust on the same property.  Here are the dimensions of this impressive black locust:

Circ. 9.92’, height 100.42’, spread 40.5’, index 229.545, rank # 2 (0.257 points shy of co-champion status), rank #2

Next we stopped to update the dimensions of the state champion sweetgum in the Ottumwa Cemetery. Since the outline of this tree is very symmetrical it gives one the impression of being a well-formed tree, but foliage can conceal serious problems. A closer inspection reveals a trunk which divides into two leaders with much included bark. Perhaps, a Cobra dynamic support system would be beneficial. Here are the updated measurements:

Circ. 11.46’, height 71.67’, spread not updated, most current measurement 69.5’, index 226.545

The next stop was to see an American elm Shane had spotted earlier. The tree stands alone in a pasture on private property near the Missouri border. It is not one of the biggest elms, but seeing this beautiful tree in the late afternoon light was a memorable sight! Here are the dimensions of the elm:

Circ.14.29’, height 62.25’, spread 97.5’, index 258.125, rank # 16


April 18th

After spending the night at Shane’s cabin, we headed toward Geode State Park to photograph the state champion sycamore. Along the way we made a couple of stops, including the Bloomfield Cemetery where two red cedars were measured. Here are the dimensions of the larger cedar:

Circ. 9.92’, height 56.25’, spread 42’, index 185.75, rank # 11

The next stop was at the historic pear tree near Lowell. The tree stands in the county road ditch on the Henry County side of the border, between Henry and Lee County. According to the adjacent owner, the tree was brought to Iowa from Ohio and was planted in the 1830’s! He also said the variety was a sugar pear. Here are the dimensions of this historic pear:

Circ. 8.42’, height 30.83’, spread 29’

The spread would have been greater but much of the crown was lost in a 1979 storm.

I was hoping for early morning photos of the champion sycamore but that would not be possible on this day. While at Geode, I decided to measure the very tall cottonwood again that stands not far from the big sycamore. Much to my dismay, I was unable to match the height I found on my previous visit. Instead of surpassing 124’ I could only get up to 122.92’, which for a perfectionist like me, is very hard to take. On my next visit, I hope I will be able to get an accurate measurement that will clear up this troubling loose end!

I had made arrangements to measure a silver maple in Danville, and that was the next stop. Here are the dimensions of the silver maple:

Circ. 17.33’, height 77.33’, spread 108.5’, index 312.455, rank # 7

In the North Hill part of Burlington we measured a redbud that I had noticed some time ago. We determined the redbud to have these dimensions:

Circ. 4.5’, height 32.58’, spread 34.75’, index 95.268, rank #3

After making some notes on potentially big trees the next tree was a hedge maple which stands on the City of Burlington right-of-way. It was disappointing to see someone had repeatedly struck the tree with a hatchet or some other instrument with a sharp blade. We found the maple to have the following dimensions:

Circ. 4.71’, height42.83’, spread 40.75’, index 109.518, rank # 1

Further east on the same street, near the former residence of Aldo Leopold, on the right-of-way, stands an oak, which I first thought might be an overcup oak. One of this size would be a new champion! Well, my first impression was not wrong, however, upon closer inspection, characteristics of both overcup oak and bur oak could be seen, likely making this tree a hybrid oak!

April 25th

I met Scott Carlson, and Davenport City Forester John Vance at Fejervary Park to measure an English Elm that I first noticed in the mid 1980’s. I would have measured the tree years ago but the tree stands just inside the fence on the grounds of what used to be the Fejervary Zoo. When I visited the park during the colder months the zoo was not open or accessible.  I want to thank Scott for making the necessary arrangements to allow me to finally measure the elm! There were two larger English elms in Burlington, but both of those trees are gone now. I’m afraid this tree may be in trouble as well, since a number of branches appeared to be dead. Here are the dimensions of the Fejervary English elm:

Circ. 11’, height 81.5’, spread 62.415’, index 229.104, rank # 1

After leaving Fejervary Park, Scott and I headed for a property in west Davenport that had a very large ginkgo, and cucumbertree.  I had not visited this property for ten years, but the last time I saw the ginkgo it had quite a few branches without leaves which I assumed were dead, but now it looked great. The cucumbertree looked really good at the time of my last visit, but now it had several sizable branches that were dead. I was disappointed to see it in that condition since I believe it is the best remaining example of the species in Iowa!  I found the cucumbertree to have these dimensions:

Circ. 11.42’, height 84.83’, spread 59.5’, index 236.705, rank # 4

The ginkgo had these dimensions:

Circ. 15’, height 74’, spread 74.5’, index, 272.625, rank # 4

On our way to a big pin oak in Davenport, I noticed a large walnut and red maple which I hope to check out in the future. It was getting late so the pin oak would be the last tree to be measured for the day. I had been admiring the pin oak for years and it felt good to finally get the tree measured! We found the oak to have these dimensions:

Circ. 14.58’, height88.33’, spread 106.25’, index # 4

April 26th

The first thing on my agenda for the day was to update the measurements of the exemplary co-champion red oak located in Dankwardt Park in Burlington. I found it to have these dimensions:

Circ. 17’, height 92.42’, spread 95.5’, index 320.335, rank # 1, (co-champion)

Over the summer a large limb was lost, revealing the limb and trunk were hollow. The spread is now less, and the tree may be coming down before too long! It would be great if some qualified arborists could assess the oak to see if it should come down.

Just north of Dankwardt Park, on Madison Ave., stands a good- sized sweetgum that I have been noticing for years. After talking to the adjacent property owner, I learned the sweetgum stands on the grounds of James Madison School. Here are the dimensions of the sweetgum:

Circ. 9.25’, height 75’, spread 55’, index 199.75, rank # 6

In nearby Crapo Park, I measured a sawtooth oak which was the largest one I had seen. I believe this species is considered invasive but I’m not aware of any problems yet here in Iowa. I found the oak to have these dimensions:

Circ. 7.83’, height 65.75’, spread 55.5’, index 173.625, rank # 1

The next tree I measured in Crapo Park was an Amur cork tree which is another non-native which can be invasive.  Here are the dimensions of the Amur cork:

Circ. 10.17’, height 58.92’, spread 54’, index 199.42, rank # 2

Not far from the Cork tree stands a respectable tupelo. I found it to have these dimensions:

Circ. 4.42’, height 54.67’, spread 41.25’, index 121.983, rank # 4

At the north edge of Crapo Park grows a large crabapple  tree. Even though the crown spread is less than it once was, it is still quite impressive. I determined the crabapple to have these dimensions:

Circ. 6.08’, height 31.17’, spread  53’, index 118.42, rank # 1

On the south side of Burlington, along south 12th St. growing on the right-of way stands a good- sized sweetgum with the following dimensions:

Circ. 8.42’, height 70.25’, spread 66.335, index 187.838, rank # 13

On south 10th St. in Burlington, I measured a red maple which had these dimensions:

Circ. 8.25’, height 56.58’, spread 61’, index 170.83, rank # 5

For years, I have admired a fine- looking white oak located near the former home of Aldo Leopold in southeast Burlington. I have stopped in the past but there has never been anyone at home. This time, once again, no one answered the door. The tree stands close to the alley, so I walked back to get a better look at the tree. While I was admiring the tree, and estimating the dimensions, someone pulled into the garage. The beautiful woman who walked out of the garage was not the owner, but she was happy to let me measure the oak! I determined the white oak to have these dimensions:

Circ. 13.5’, height 67.5’, spread 90.75’, index # 17

May 3rd  

After the article in “Our Iowa” about my work with big trees, I received a number of leads on potential big trees. One of these responses was concerning a very large cottonwood located near Holy Cross in Dubuque County. I wasn’t sure if it would qualify as single trunk or not but giving it the benefit of the doubt, I found it to have these dimensions:

Circ. 27.83’, height 102’, spread 107.5’, index 462.875, rank would be # 3

I sent photos to an expert on the subject of multi-trunk trees with the Native Tree Society and in his opinion, the tree was made up of at least three trunks. Darn it!

in 2012 my good friend Richard and I were exploring White Pine Hollow (WPH) when we came across a tall well-formed walnut.  In 2015 Richard took his life, and I referred to this tree as Richard’s Walnut. For over ten years I had been wanting to re-measure the tree to see if it was really the second tallest walnut in Iowa.

Back then I was using a handheld GPS unit. I learned the hard way; it was not always functioning properly. It took a while for me to figure out that the GPS unit was sometimes showing the GPS coordinates for the previous stop instead of giving me new ones. When I attempted to return to verify the height, I learned the GPS coordinates were not correct. Although I didn’t spend a great deal of time searching for this tree, it took eleven years before I was confident that I had rediscovered Richard’s Walnut! I had seen this tree once or twice since 2012 but because it wasn’t 127’, I didn’t think it was the right one. In 2012, I was not yet using the 200X Laser Range Finder and if a mistake was made in one of the steps to calculating the height, it would make the measurement inaccurate. Mistakes were infrequent, but I had recorded a height of 127’ for this tree. Not only were the coordinates wrong, but the height was inaccurate as well. On May 3rd I determined the circumference, spread, and actual height for this tree. Here are the dimensions of Richard’s Walnut:

Circumference- 10.25’, height 114.08’, spread 84.75’, index 258.268, rank # 22

Next, I measured the tallest tree in WPH which is also the second tallest tree in Iowa. Here are the dimensions of this exceptional white pine:

Circ. 10.17’, height 150.58’, spread 50.17, index 285.123, rank # 4

We now have two trees in Iowa, both white pines, that exceed 150’!

May 4th

It had been several years since I had visited Merritt Forest State Preserve, and I was anxious to update the height of the tallest known bitternut hickory in Iowa. The most recent measurement for the tree was back in May of 2013. At that time, I determined the height to be 113’. I was hoping the tree was still standing and that it would have added several feet of height. After searching for the tree, I was unable to find a trace! Upon arriving at Merritt Forest Preserve, it was immediately obvious that this small tract of forest, which is considered to be the best example of a virgin forest in Iowa, had been subjected to one or more severe storms.  It was sad for me to see this very special place had lost so much since I saw it last!

I did find a red oak that must have been one I measured previously but it was hard to recognize, since it did stand in the timber, and now it was mostly in the open. On April 23, 2011 this tree had a height of 113’ on this day I found it to have these dimensions:

Circ. 14.33’, height 115.42’, spread 83’, index 308.12, rank # 7. This height matches the height of the tallest known red oak in Iowa, which stands in Wildcat Den State Park!

I realize there are not many other people in Iowa that would care about a tall dotted hawthorn, but I was very excited to find one in White Pine Hollow. Here are the dimensions of the new Iowa height record for a dotted hawthorn:

Circ. 1.79’, height 37.75’, spread 33.5’, index 67.625, rank # 2.  This tree shares co-champion status with a Franklin County tree that has a total of 67.75 points.  I have measured very few dotted hawthorns so I’m sure there are larger ones out there to be found.

This would be the last tree I would measure for the day. I’m proud of myself because I made it out of WPH before it became dark!

May 5th

I returned to WPH with a focus on updating the heights of some previously measured walnuts. In 2012 I measured a walnut that had these dimensions:

Circ. 7.75’, height 119’, spread 56’.

Here are the updated measurements:

Circ. 8.92’, height 123.17’, spread 59’ index 244.92, rank # 33. This is now the second tallest known walnut in Iowa.

In April of 2017 this walnut had these dimensions:

Circ. 8.92’, height 118.75’, spread 66.5.

The dimensions on May 5th 2023, were as follows:

Circ. 9.17’, height 119.33’, spread not measured, index 245.955, rank # 31

The next walnut, which I had never measured before had these dimensions:

Circ. 7.33’, height 123’, spread 55’, index 223.75’, rank # 42

There was a time when you could drive from the east side of WPH quite a ways to a parking area well into the preserve. Flash floods washed out the road in places a couple of times so the old road is now just a walking path. The largest shagbark hickory in WPH stands not far west of the old east parking lot. Here are the dimensions from November of 2012:

Circ. 7.23’, height 104.3’, spread 56.5’, index 202.655.

May 5th 2023 dimensions:

Circ. 7.5’, height 109.33, spread 58.25’, index 215.733, rank # 2

After visiting WPH, I headed to nearby New Wine County Park to check on a serviceberry that I originally identified as a roundleaf serviceberry. I had told Jeff Carstens about this specimen and he visited the site for possible seed collection just prior to my arrival, and there was some confusion concerning the location, size of the tree and the tree identity.  Based on the very round leaves I observed when I first saw the tree in 1984, I identified the tree as a roundleaf serviceberry, Amelanchier alnifolia. According to Jeff, the tree is actually an Allegheny serviceberry, Amelanchier laevis. It only took 39 years to get a proper identification!

The tree that is standing today is actually not the same tree I first measured in 1984. I didn’t know it, but that tree came down recently, and the one that Jeff looked at was a younger tree that suckered from the roots of the older serviceberry. This explains the discrepancy in the size. Until now, there had been no Allegheny serviceberry on the spreadsheet, so even though we had to remove the only A. alnifolia from the list we were able to change it to A. laevis! Here are the dimensions of the only Allegheny serviceberry on the Iowa Big Tree Spreadsheet:

Circ. 1.125’, height 39.08’, spread 17.5’, index 56.955, rank # 1

My next stop was Mines of Spain State Recreation Area, just south of Dubuque. I had long thought this might be a good place to look for big trees but there was always so much to do in White Pine Hollow there was never time for Mines of Spain! I wasn’t able to hike my first choice of trails because of high water but there were some significant trees to be found on my second choice of trails. Here are the dimensions of a honeylocust which has the fewest points but the greatest height:

Circ. 8.25’, height 106.25 (new height record for Iowa), spread 49.5’, index 217.625, rank # 16.

The timing of this trip was perfect for comparing American plums with Canada plums. Here is a brief description of the differences I noticed on this trip. The American plum is found in open sunny areas, whereas the Canada plum can be found growing in the understory of open woodlands. The flower of the American plum typically has a reddish tint whereas the Canada plum has very white flowers that are larger than the American plum. I had never measured a Canada plum before and I’m sure there are many larger ones, but here are the dimensions of the only Canada plum to be nominated so far in the Iowa Big tree Program:

Circ. 1.75’, height 21.75’, spread 14’, index 46.25, rank # 1

May 8th

Although I returned from my last tree hunting trip on May 5th, and I was still tired, I was anxious to see a large cottonwood in Mitchell County. This is one of those trees I would likely never have found on my own, so thanks to Dennis Riley for the heads up on this cottonwood. My first stop though, was to check on the state champion cottonwood from Franklin County. I’m glad I already had photographs of this tree because a large dead limb that was broken but still hanging on to the trunk was important for the composition of my best photographs. Since my last visit, that big limb had completely let go. When this big limb finally came down, it took a strip of wood and bark from the trunk which reduced the circumference!

I thought that I had looked at the cemetery in Hampton many years ago, but after stopping there, it became obvious, I had never scouted out this cemetery. There are only a few cemeteries in Iowa that set themselves apart from all the rest because of multiple significant trees, and Hillside Cemetery in Hampton is in that category. The most significant trees in the cemetery are the white firs. Three of these are larger than any others on the spreadsheet!  Here are the dimensions of the three largest white firs:

Circ. 11.33’, height 87’, spread 40.5’, index 234.5, rank # 1 (co-champ)

Circ. 10.92’, height 94’, (Iowa height record) spread 36.5’, index 234.188, rank # 2 (co-champ)

Circ. 11.33’, height 85’, spread 47.75’, index 232.938, rank # 3 (co-champ)

As exciting as this find was, there always seems to be some bad with the good. None of the white firs are in very good shape. The largest one has a trunk that bifurcates, and I don’t know how it has not yet split! Does anyone have experience with Cobra bracing? I wonder if it might help keep the leaders from splitting for another decade or two. One of the leaders could be removed but it would make a huge wound and then the remaining leader may be more prone to breaking.

The second largest one is in the best shape structurally but this one appeared to have more sparse foliage. For years I have been trying to find a white fir that reached or surpassed 90’. There were two white firs in Newton that were close to 90’, but one of those has been gone for years and the other one lost its’ top in the 2020 derecho. Finally, a white fir has been documented with a height of over 90”!

The third largest one has lots of multiple leaders, and in my opinion, it is the least attractive of the three big white firs here.

The 6th largest white fir also resides in Hillside Cemetery. This one is no slouch with a circumference of 10’ and a height of nearly 86’.

These four white firs alone would be enough to put this cemetery on the Iowa big tree map, but there are more big trees here. There is a Norway spruce with a circumference of 10’11”.

There is a very respectable white cedar that had these dimensions:

Circ. 9.75’, height 53.5’, spread 40.75’, index 180.688, rank # 6

A white spruce in Hillside Cemetery had these dimensions:

Circ. 7.25’, height 91.67’, (tallest) spread 33’, index 186.92, rank # 2 (co-champion)

I also measured a blue spruce that had the following dimensions:

Circ. 7.58’, height 87.58’, spread 42’, index 189.08, rank # 2 (co-champion)

Hillside Cemetery in Hampton has the three largest white firs, including the height record, the co-champion white spruce which is the current height record, the co-champion blue spruce and the number 6 white cedar!

I should not have spent so much time in Hampton, but I couldn’t tear myself away from all of those magnificent conifers in Hillside Cemetery. If I wanted to measure the big cottonwood in Mitchell County, I would have to make tracks with no stops along the way! It took much longer than I anticipated to get from Hampton to the cottonwood, located near Otranto just a couple of miles from the Minnesota border.

As I was driving towards the tree, I could see there was a thunderstorm just to the west of where I thought the tree would be. For the last- half hour before reaching the tree, I was nervously watching the numerous lightning strikes just a few miles west of my destination.  I was driving a little faster than normal, so I might get there before the storm hit. When I finally arrived at the site of the cottonwood, I was somewhat surprised the rain was not yet falling. Perhaps I would have time to measure the tree after all! It was eerily dark as the ominous storm clouds approached. Even though there should have been a larger window of daylight, the darkness created by the nearby storm made it appear to be later in the day. With the impending storm, I would have to hurry with my measurements without sacrificing accuracy.

After viewing the cottonwood, I wasn’t certain it had a single trunk, but I couldn’t see anything glaring that would prove it was multi-trunk, so I gave it the benefit of the doubt.  The tree stands in the road ditch, and it appears to stand on both private property and county property. After considerable deliberation, I settled on a point that I thought best represented 4 ½’ above the ground. After measuring the circumference, I was able to measure the height without too much trouble. Before measuring the spread, I decided to take a few photos before it became too dark.

The cottonwood stands in the bottom of the ditch and the road is much higher than the elevation of the tree. Scrambling up and down that steep road bank would be a challenge under any circumstances but with barely enough light to see the eroded gullies, it was becoming more treacherous as the sky continued to darken.  I was racing to get the spread measured before the storm hit but I was running out of time. Before I could get a second spread measurement, the lightning had reached the vicinity of the cottonwood, which forced me to reluctantly give up my quest to complete the measurements! I would have to return another time to finish measuring the spread.  I determined the cottonwood to have the following circumference and height dimensions:

Circ. 29.83’, height 102’,

Soon after leaving the cottonwood the rain started coming down and by then it was completely dark.  After three long hours of night driving with numerous highway changes, I finally reached Guttenberg where I would spend the night!

May 9th

My first stop for the day would be to check out two cottonwoods on private property in western Clayton County near the Volga River. I measured one of these trees in 2016 but the other one had never been measured. The one that had been measured previously stands close to the Volga River and the base shows no flare. This tells me silt has built up around the tree so measuring 4½’ up from the current ground level would not represent 4 ½’ above the point of germination. The owner’s Bob and Brian Decook drove me to the tree, and Brian was chosen to dig next to the base to try and determine the original ground level. After digging down perhaps one foot, a rod was pushed further into the soil until the basal flare was hit. We conservatively estimated the level of the ground where the tree germinated was more than two feet lower than the current level.  I proceeded to place the tape measure around the trunk at a point that much more closely represented  4 ½’ above the point of germination.  This extra work would allow for a more accurate circumference and height measurement while adding more than a foot to the girth and more than two feet to the height. Here are the dimensions of the cottonwood:

Circ.21.33’, height 118.25’, spread 86.25, index 394.563, rank # 8

The second cottonwood stands on a slope some distance from the previous tree. Here are the dimensions of this cottonwood:

Circ. 22.17, height 106.5’, spread 80’, index 392.5, rank # 10

The cottonwoods stand on the south side of the Volga River, but the Decook’s own property on the other side of the river as well. It was on the north side of the river where I was shown a large American plum. The tree is mostly dead which is not surprising for a plum of such great size. I have only seen one other plum that rivals the circumference of this tree.  In 1995, I measured one from Floyd County that had a total of 66.25 points. Here are the dimensions of Clayton County plum:

Circ. 3.42’, height 19.17’, spread 13.5’, index 63.545, rank # 1

The next stop would be Echo Valley Park. I didn’t find too much here to get excited about, but I did find a good-sized chokecherry. Here are the dimensions of the chokecherry:

Circ. 1.46’, height 38.33’, spread 20’, index 60.83, rank # 2

May 10th

After another night in Guttenberg, I headed for Sny Magill where I looked for trees along Sny Magill Creek. I saw several nannyberry and several American plums here. I measured an American plum with 51.705 points and a ranking of # 2. I don’t see nannyberries in central Iowa, so I enjoyed seeing several in northeast Iowa.

My next stop was Brush Creek Canyon in Fayette County.  This is some place that I have wanted to visit for many years, and I did make it there a few years ago, but it was so foggy I couldn’t see the trees! This time the visibility was good, but a two-hour hike didn’t reveal anything significant.

The next stop was Harlington Cemetery in Waverly. I found a Norway spruce here with a circumference of 12’5” but because it was getting late, I decided to measure the height and spread later, if there was time. I also measured a red cedar and a Douglas-fir. Here are the dimensions of the Douglas-fir:

Circ. 8.58’, height 80.33’, spread 44’, index 194.33, rank # 7

It was now 7:30, but I was still hoping to measure one more tree. I wanted to stop in Clarksville to measure a large American elm that I first notice many years ago. There were two good sized red elms in Clarksville that I was anxious to measure, but I discovered they were both gone! I was able to measure the American elm, but I don’t think I hit the highest twig, so the height is probably greater. This tree has managed to survive all the waves of DED, but it has not done well with storms. The spread in particular is much reduced from what it used to be. The spread probably would have been in excess of 120’. While talking to the owner, I learned they were planning to have the tree taken down. I’m not sure if it really needs to come down but it does stand close to the home and the family was concerned about safety.  I finished measuring the elm just as it was getting dark so that would have to be my last tree for the trip.  Here are the dimensions of the Clarksville elm:

Circ. 15.875, height 76.33’, spread 90.5’, index 289.455, rank # 11

June 11th

My first stop of the day was in Mason City where I noticed a large cottonwood. The trunk measured 22.67’ but unfortunately it has a lower limb which probably divided from the main trunk near the ground so it would not qualify as a single trunk. I made notations for a large basswood in Mason City that I hope to measure another time. I had made arrangements to measure a reported big cottonwood not far to the northeast of Mason City. On the way there I noticed another big cottonwood, but I had to pass it by in order to keep my pre-arranged appointment to measure another cottonwood, which turned out to have the following dimensions:

Circ. 24.17’, height 83’, spread 76.5’, index 392.125, rank # 11

The next stop was to complete the unfinished business of measuring the spread of the big cottonwood near Otranto.  At the location of the big cottonwood, I met Dennis Riley, and Andy Taets.  Dennis is the one who told me about the tree and Andy is with Mitchell County Conservation. Both men are nominators of this big cottonwood. Andy took video of me standing in front of the tree which may still be accessible by visiting the Mitchell County Conservation website. Apparently, the video can also be seen on YouTube. After measuring the crown spread, I had complete measurements for this giant cottonwood. Here are the dimensions:

Circ. 29.83’, height 102’, spread 114.5’, index 488.625, rank # 1 (co-champion)

After leaving the Otranto Cottonwood, Dennis Riley showed me a very large Norway spruce in Osage. I was in a hurry, so I didn’t take the time to measure the spread but here are the circumference and height dimensions:

Circ. 13.17’, height 92’, spread, approx. 50’, index, approx. 262.5, rank, approx. # 6

A longtime friend of mine from the Lake Mills area offered me a place to spend the night, so I accepted his offer.  The price was right, but I didn’t get much sleep on the Futon in his liquor store. That was the first time I ever spent a night in a liquor store. Come to think of it, it was the first time I had ever been in a liquor store!

June 12th  

A quick look around Lake Mills revealed a good-sized green ash with no signs of EAB. Lake Mills and several other towns in northern and northwest Iowa still had ash trees! I also noticed a large bur oak in Lake Mills which I hope to measure another time.

There are very few champion trees on the spreadsheet from northwest Iowa, but one town accounts for two of these champions. The town of Armstrong, located in Emmit County has had the champion tamarack for several years, but now it also has the champion ponderosa pine!  There are two large ponderosa pines in the city park, and here are the dimensions of the larger pine:

Circ. 9.83’, height 61.75’, spread 56.75’, index 193.875, rank # 1

Before toppling from the 2020 derecho, the former champion ponderosa pine from Cedar Rapids stood 92.42’ tall! There are also two large ponderosa pines in Atlantic, which I believe would have more volume, but the Armstrong tree wins on points.

The champion tamarack stands in gravel covered church parking lot. Here are the dimensions of the largest known Iowa tamarack:

Circ. 8.17’, height 65.08’, spread 51.5’, index 170.92, rank # 1

There used to be a tamarack in Indianola that was nearly as big as the current champion, but it was cut down in 2000. I suspect the tree was cut when the “evergreen” lost its needles and appeared to be dead. If this tree were still alive today, it would have been considerably larger than the current champion! Also in Armstrong, stands a white spruce that I have not yet measured that is worthy of inclusion on the spreadsheet.

I didn’t stop to measure any additional trees until I reached Spencer, where I measured a paper birch with these dimensions:

Circ. 7.58’, height 47.83’, spread 48.25’, index 152.893, rank # 8

I was contacted several months earlier by Joyce Kaiser of Sioux City concerning a large cottonwood in Archer, Obrien County. When she was young, Joyce used to live in a house adjacent to the property where the big cottonwood stands. Joyce is an older lady, and she remembers the cottonwood being very large when she was a kid. Joyce and I had exchanged many emails regarding the big cottonwood, and finally it was time to see the tree for myself. I was not disappointed! Here are the dimensions of this impressive cottonwood:

Circ. 25.375’, height 102.17’, spread 85.25’, index 427.983, rank # 5

The most impressive thing about this tree was the trunk which was devoid of limbs for some distance. Joyce describes the tree as the last remaining claim tree in Archer. Apparently, trees were planted to mark the boundary of land claims.

After leaving Archer, I headed to Sanburn, which is also in Obrian County. I met a couple there, and they showed me a cottonwood in rural Ashton, which is in Osceola County. I measured the cottonwood and here are the dimensions:

Circ. 22.5’, height 91.75’, spread 102.75, index 387.438, rank # 15

In Ashton, I made notes on some large blue spruce, and a basswood before heading to Hinton, north of Sioux City. At Deer Run Golf Course, I met with a man who gave me a heads up about a very large cottonwood located on the golf course. Despite having a low limb growing against the trunk, which  exaggerated the girth, this was a very impressive tree! I don’t have the equipment to determine a functional circumference, so I measured the tree using the standard method. Keep in mind the trunk circumference would be several feet less without the influence of the merged limb. Here are the dimensions of the Hinton Cottonwood:

Circ. 27.71’, height 114.25’, spread 133.5’, index 480.156

It is too bad the trunk cannot be considered single because it would rank as a co-champion! I would like to measure the tree using the functional circumference technique to see just where it would rank.

From Hinton, I went to Sioux City, and although it was getting late, I was hoping for one more tree. I just had to stop and check on the state champion white pine in Logan Park Cemetery. It was nearly 8:30 by the time I arrived, but there was just enough daylight left for me to measure the circumference and height.

I didn’t expect to see much of a change in dimensions because it had been so dry, but I measured the circumference and height anyway. I last measured the tree on January 11, 2022 and at that time the circumference was 13.42’ (13’5”). The updated girth was 13.48’ (13’5 ¾”). Hopefully the tree had enough moisture over the rest of the summer for the trunk to reach 13’6”. In January of 2022, the height was 119.67’. When I measured the height this time, I found it to be 120’! Because of the drought, I’m not certain it actually grew 4”. I think I may have hit a previously missed high point.

It would be wonderful if there was a way to get a lightning protection system installed for this very special tree! If anyone has any thoughts on how this might be accomplished, please let me know! I was planning to go home but getting a motel sounded better than arriving home late after a very long drive. I found a motel in Sioux City and the price was right. After all, who needs a sparkling clean room or a TV?

June 13th  

First thing in the morning, I returned to Logan Park Cemetery. I took some additional photos of the champion white pine, but I don’t think they were an improvement over what I had already. I updated the circumference of the # 4 black Cherry and learned it was now 11.29’, which was an increase of 1.5” since it was last measured in January of 2022.

My next stop was the Jeffers Memorial Holiness Camp, located just north of Sioux City. I was told there was a big cottonwood here. There was indeed a large cottonwood, and I determined it to have these dimensions:

Circ. 22.54’, height 97.58’, spread 103’, index 393.83, rank # 9

Just on the other side of the creek from the Jeffers property is a cottonwood with these dimensions:

Circ. 19.92’, height 86’, spread 85’, index 346.25, rank # 28

Another big cottonwood on the Jeffers property that I did not measure would have a circ. of at least 18’. From here, I headed home, but I was still on the lookout for big trees. I looked around Sac City and I was impressed with the high number of bur oaks and the world’s largest popcorn ball! My next stop on the way home was Rockwell City, where I measured a green ash and a downy hawthorn in the city park. The ash, which was just starting to show signs of EAB, had these dimensions:

Circ. 13.67’, height 75.58’, spread 69’, index 244.83, rank # 7

The downy hawthorn was respectable with 95.941 points, giving it a rank of # 5. My next stop was to check on the # 2 balsam fir in Webster City. This tree grows very close to the alley, and previously I was uncertain if the tree was on private or city property. After inspecting the site, I believe the tree stands on private property. I was fortunate because the owner was home, and they were very cooperative. The dimensions of the fir are impressive, but it doesn’t look healthy. It has many dead branches, many of which still retained the rusty dead needles. Does anyone have any ideas as to what might be causing this problem? I found the tree to have these dimensions:

Circ. 6’, height 79’, spread 18.5’, index 155.625

June 18th

I went back to the Mason City area to measure a cottonwood that I noticed on my previous trip. Luckily someone was home, and I was able to measure the tree. Here are the dimensions of the cottonwood:

Circ. 22.17’, height 86.33’, spread 110.835’, index 380.035, rank # 19

A few miles north of Mason City I spotted a sizable blue spruce that will likely not be a champion, but it appeared to be one of the biggest. I stopped, but no one was at home, so that will be a tree to measure on a future trip.

Not counting the tall cottonwood at Geode which had been measured previously, I measured twelve cottonwoods during this half of the year. Not counting three of these that are likely multi-trunks, that still leaves eight cottonwoods with trunks that measured over 20’!  No counties have as many big cottonwoods as Polk County, and Woodbury County.  Both counties currently have four cottonwoods with a circumference of over 20’!

Photographs of some of the trees described above are included below.


In Ottumwa, the proud owner stands with her right hand on the champion black locust, and her left hand on the number two black locust! Shane Hammond stands on the left-hand side of the photograph.

The adjacent owner stands next to the historic state champion pear tree, located near Lowell, in Henry County.

Jeff Carstens found this massive sycamore in Lee County. Although the trunk divides quite low, it appears to have a single trunk. With an average spread of 148’9”, and a maximum spread of 155’, this sycamore has the greatest spread of any Iowa tree!

Here is another photograph of the sycamore with the greatest spread. It appears the trunk originally bifurcated at about 4’ above the ground.

For comparison, here is the state champion sycamore from Geode State Park. The crown spread is only half as great as the previous sycamore, but the trunk is unparalleled!

Here is another photograph of the champion sycamore. The trees in the understory, with leaves, are Ohio buckeyes.

Shane Hammond stands next to this beautiful American elm which he found near the Missouri border in Davis County.

The fourth largest ginkgo in Iowa, grows on high ground in western Davenport. To provide scale, Scott Carlson and the owner stand next to the big ginkgo. This impressive tree has a circumference of 15’.

With a height of 84’10” this cucumbertree, located in on the same property as the ginkgo in the previous photograph, is likely the tallest one in Iowa. One in Burlington that was 98’ tall has been gone for over ten years.

This cottonwood from Dubuque County has a circumference of 27’10”, but it appears to be three fused trunks.

The seventh largest red oak in Iowa stands in Merritt Forest State Preserve in Clayton County. With a height of 115’5” it ties the height record for the species.

Here is a view looking up at the state champion rock elm from White Pine Hollow in Dubuque County. Rock elms resemble American elms, but they typically have a straight trunk with a relatively narrow crown and the leaves are smaller.

Here is another photo of the champion rock elm. This tree was described in an earlier report but my most recent visit provided an opportunity for improved photographs. Growing towards the bottom of a northeast facing slope, this champion reaches a height of 111’7”.

This new co-champion white fir reaches an impressive height of 94’, and the circumference measures 10’11”. Two other white firs, also in the Hampton Cemetery have a trunk circumference of 11’4”! This tree is within ½ point of the largest white fir which also grows in the Hampton Cemetery!

Assuming this cottonwood from Mitchell County has a single trunk, it qualifies as a new state champion! The height and spread dimensions are impressive but the circumference measures 29’10”, which is exceptional!

This cottonwood from Archer, in Obrien County in northwest Iowa, is among the most impressive cottonwoods I have ever seen. It has a definite single trunk that measures 25’5”. The lady in the photograph, who is the primary nominator, grew up only a couple of houses from the tree.

This cottonwood located north of Sioux City has a circumference of 22’6”.

This cottonwood grows in the town of Hinton, in Plymouth County. Unfortunately, the trunk includes a fused limb, so it doesn’t qualify as having a single trunk. Including the fused limb, the trunk measured 27’9”, height was 114’6” and the spread was over 133’. The man in the photo is the nominator and he stands 6’3” tall.

Bob Decook, wearing the black shirt, and his son Brian, pose next to a cottonwood on their property near Volga, in Clayton County. The tape measure, visible near the bottom of the trunk, was placed there because at least 2 ½’ of silt had accumulated around the base since the tree germinated.

The Decook’s cottonwood ranks as the eight largest one in Iowa, and if volume were to be determined, I think it would rank higher. Although it’s not as close to the Volga River as it appears in this photograph, it is still too close for comfort!