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Long ago during the Coal Age the rugged Ozarks were the western coast of North America as rising and falling sea levels caused the scene to alternate between shallow tropical seas and coastal swampland. Continental drift had placed ancient Arkansas on the equator and the collision of land masses caused a great arc of rugged mountains to extend from eastern Canada around to become the ancestral Ouachita range. This collision had produced a single continuous land mass (Pangea) extending all the way over the south pole. That, in turn, caused great ice sheets to come and go, as driven by periodic shifts in the shape of the earth’s orbit – the same shifts that have caused ice sheets to come and go in our present Pleistocene era. With the gentle slope on the edge of our continent, river deltas extended back and forth between southern Illinois and central Arkansas as ice sheets expanded and contracted. All the while, the advancing continental collision and build-up of sediments derived from mountain ranges being created caused river deltas to extend ever farther into our area. The sandstone deposited by those deltas would become the backbone of the Boston Mountains we hike on today. [...]

BOOK REVIEW: The Nature of Oaks – The Rich Ecology of Our Most Essential Native Tree, by Douglas W Tallamy, 2021, 197 p. In this book an entomologist follows oaks through the year in describing the ecology of the tree. The Ozarks lie in what is nominally the oak-hickory forest zone, and witness trees studies show that oaks composed about 70% of the early historic forest when first encountered by land surveyors. This book presents oak ecology from a caterpillar’s point of view through the eyes of a veteran bug scientist, and there’s a lot going on behind the scenes. One of the most important class of oak predator, the weevil, uses “beaks” to drill eggs into acorns. Maturing larvae then make an exit hole to get into the ground after the acorns fall, while ant colonies use the convenient exit opening after they leave. Retention of withered winter leaves on lower branches of oaks is seen as a deterrent to browsers seeking nutritious buds. The author cites extreme variation of tree host species and their load of insect (caterpillar) consumers. Oaks have the largest array of such consumers compared to few for tulip tree and black gum. He suggests [...]

In a recent visit to Pea Ridge Military Park, I was interested in seeing progress in eliminating invasive red cedar from the grounds. Cedar is notorious for invading old pastures in our area. Another tree that thrives in old fields is our white ash, a stately tree of upland forests. So, it was not unexpected to see large white ash trees left in the open forest when cedars are removed. What I had not expected to see was that these newly released ash trees (Pea Ridge photo) had large numbers of bare branches. I checked with a park ranger on his rounds and he verified that the emerald ash borer is now present at the park. We knew it was on its way and that all attempts at stopping the advance had been given up as futile (see the chapter of forest diseases in Ozark Forest Forensics). Pea Ridge 2021 This will be a serious loss to our old growth forests. And it’s not just white ash on uplands. Green ash is a major part of forests adjacent to wet prairie environments and stream bottoms. Blue ash is a relatively rare but important tree around limestone ledges such [...]

You see them in the leaf litter in late summer on hikes in our oak and hickory woodlands. They look like tan golf balls, complete with the stippled surface texture that helps golf balls fly a little farther than they would with a smooth surface. But these balls are light as a feather, with parchment thin skin and an array of cobweb like strings for an inner texture. Ozark hikers often wonder what sort of fruit these are and where they came from. It turns out these are but one of many different varieties of leaf gall created by insects as part of their life cycle. There are lots of different structures developing out of oak leaves when their growth process is hijacked by insect pests for their own purposes. More than 800 insect species create galls on oak twigs, and over 700 of them are wasps. These particular galls are so perfectly symmetrical that many observers figure they must be some kind of exotic fruit and not just a deformed oak leaf. Some leaf galls are not nearly as noticeable as the papery balls described here. In the case of the round “golf ball” structures in question we have [...]