A new species found in the wild to add to the Flora of Winnebago County
By Alan Branhagen, NLI’s Executive Director
Mockernut Hickory at NLI’s Howard D. Colman Dells Nature Preserve. Photo by Alan Branhagen
On Saturday afternoon, January 18th, I was out birding to add to my 2025 bird list. I stopped in downtown Rockford at the dam and at Blackhawk Park but found no new birds in the open water. It was the day after a record high of 54F and a cold, though seasonable day. Tomorrow was predicted to be bitter cold as an Arctic front was in the process of moving in.
I decided to drive southwest into the open country, out Montague Road, then south on Meridian – I decided that stopping by Howard D. Colman Dells Nature Preserve (NLI)-Howard Colman Hall Creek Preserve (Byron Forest Preserve District)-R. Robert Funderburg Forest Preserve (Forest Preserves of Winnebago County/FPWC)-Severson Dells Forest Preserve (FPWC) conservation land complex would take me on a walk into the woods and sheltered from the incessant north wind. I parked in the Howard Colman (Byron) Forest Preserve parking lot. There’s a good sign near the trail entrance there showing the over 1,700-acre complex that the Forest Preserves of Winnebago County, Natural Land Institute (NLI) and Byron Forest Preserve District protect.
I started down the trail which leads down the old Weldon Road bed towards Hall Creek. NLI land (not open to the public) is on the north/left and Byron Forest Preserve land on the right. I was thrilled to see an adult Red-headed Woodpecker alight above me and put on a show in perfect lighting. Bird number 61 for 2025! I thought about how they were so common when I was a boy and now are much less common and localized. They prefer open savanna or woods with many standing dead trees – the demise of ash trees by emerald ash borer (EAB) seems to have helped them recently. I always marvel at their striking pattern, red-red head, and otherwise black and white: spiffy bird indeed.
I was planning to walk down to look over Hall Creek and when I got there most of it was frozen over so I decided to keep walking up the trail. Riffles in the creek were open and the sound of the flowing water most pleasant – it just takes any stress away as one gets absorbed in the moment with comforting sounds. Yes, this valley was out of the wind and the flowing water and sounds of birds and Nature were all one could hear and see. I was thankful for the three organizations putting together this amazing conservation complex for residents to get ensconced and immersed in nature. I’ll also admit I find comfort in being in the forest, and this is one of the largest remnant blocks of forest around.
I was looking at all the marvelous trees and how last summer’s derecho had damaged many. Others were resilient: one of the biggest Black Walnuts I know of weathered that storm and I contemplated whether we should nominate this tree as a Legacy Tree. As they are valuable trees that have been known to have been rustled (cut and stolen for their highly prized wood) I wondered if that was a good idea. Black Walnuts are amazing trees full of life, but I’m all for proper management of them and cutting select trees for their valuable lumber. The tree has actually become aggressive in local woodland, out competing our keystone oaks and hickories to their detriment. I still advocate protecting old veterans like this one.
A close up look at the bark of the Mockernut Hickory at Howard D. Colman Dells Nature Preserve. Photo by Alan Branhagen
I decided to keep walking and reached the Funderburg Forest Preserve, though NLI’s Colman Dells Nature Preserve is again on the left of the path. The Colman Dells property is a dedicated Illinois Nature Preserve and has old growth trees and I was admiring a large shagbark hickory that stood tall while a neighboring one had snapped off up high in last summer’s storm. In between these two trees was another large hickory – and its bark not shaggy like a shagbark nor smooth like our other species of local hickory the Bitternut Hickory. Having lived in Missouri for 21 years I thought it looked like a Mockernut Hickory (Carya tomentosa) which is not known to occur this far north. I got off the trail and walked up to the tree – I looked up in the crown with my binoculars and could see remnants of the hickory nut husks! That’s another sign it had to be mockernut because its nut husk doesn’t completely separate and drop like shagbark and thus can hang on the tree into winter after the nuts have dropped. Then I noticed a fallen branch from the derecho of the tree at the base and I could see the stems and nuts from last summer: twigs were fuzzy “tomentose” as the Latin name of the tree describes – Check! The nuts’ husks were thick and had split partially but not to the base – Check! I do believe with all these characters this is a Mockernut Hickory – a new species of tree found in the wild for Winnebago County (though I’m just a few hundred yards north of Ogle County).
Nut husks from the Mockernut Hickory tree at Howard D. Colman Dells Nature Preserve. Photo by Alan Branhagen
Mockernut Hickory has that name because the nutmeat is delicious but makes a mockery of anyone trying to extract it from the hard shells of the nut. Pecans (also hickories) are easy-peasy but not this species!
Because it was late afternoon, I thought I would come back with NLI stewardship staff to look for other trees – how can there be just one? Are they self-fertile or do they need cross-pollination like most hickories? I forgot to break open leftover nuts to see if they had remnant nutmeat in them or were they “blanks” and infertile. I was guessing the tree was at least 70 years old based on my decades of observing various hickory trees I’ve planted, in botanical gardens or in the wild.
Mockernut Hickory is most definitely a climate resilient species, drought resistant, heat-loving, and otherwise long-lived and rugged. They have lovely yellow fall color and are host to many insects just like our locally native hickories. Their nuts can’t escape the teeth of squirrels but many end up being planted by such critters when they are buried as larder for future use – not all get recovered. I actually had planted them before in my Missouri acreage as they came in a bundle of mixed hickory from the state nursery. I also have seen the tree before in the county because there is at least one in the Klehm Arboretum that is remnant from the old Taylor Nursery but not as big as this tree.
2025 and yet there is still more of our local biodiversity to be discovered. I’m thankful this tree resides on protected lands. As potentially the northernmost of its kind, it certainly has good genes for hardiness, though most hickories are far hardier than where they currently reside. They are all expanding northward with the changing climate since the last ice age – a slow process when squirrels are the likely agent and Blue Jays generally moving the opposite direction in fall when the nuts are ripe. When people do the moving of nuts, we call it assisted migration. I just had to share my serendipitous discovery – and know there are many others out there doing the same. Now, we need to make a collection of the plant to verify it and deposit it at an appropriate herbarium. I have to end with I always experience something new on every visit into Nature – though this time that was extraordinary.
Read here about a Shagbark Hickory in Sinnissippi Park, Rockford, Ill. that was the featured January (2025) Tree of the Month as part of NLI’s Legacy Tree Program.