Tag: open canopy

A Science for Everyone

Measuring Forest Canopy

michaelmccurryphd

I like foresters – they have some fun tools.  In grade school, I learned how to use an increment borer to determine a tree’s age and it’s rate of growth.  Later, I learned how those tools, coupled with beams in cliff houses and other old dwellings in the American Southwest helped develop the specialized science of dendrochronology – determining dates by the study of growth rings in trees.  It turns out that it also provides a lot of information about past climate and weather.

This week, I got my hands on a spherical densiometer.  It’s a simple little tool, designed to measure the density of the forest canopy.  Fits in a shirt pocket, and shows that it was developed by a forester in the correction factor – you multiply your count by 1.04.  Others might try for a 1:1 reading – but a forester deals with Scribner scale, Doyle scale and International scale for measuring logs, and knows that what is correct with one method gives a different answer if you change methods.  1.04 is close enough in forestry.

I want to get a better handle on canopy because of a comment Joe Zacek made over 40 years ago in a conversation with Tim Wiersum.  Joe was a range scientist – one of the best – and Tim was trained as a forester.  They were closing in on a magic number in forest canopy figures . . . and figured that somewhere between 25 and 30 percent canopy would provide 100% of harvestable timber and 80% of potential grass.  I figured it was all a matter of sunlight – but as I’ve grown older, I’ve noticed that the open areas tend to have a bit more soil moisture in the Spring. 

Other studies have been done on canopy (or crown density) and the spread of fires.  I’m certainly no expert, but using the densiometer on the old road shows me that a road that made a good firebreak 70 years ago isn’t anymore. 

It’s a simple little tool – but if I can carry it in my pocket, improve grass growth, timber growth and fire safety, I’m going to enjoy using it.  A real forester might be better, but I’m happy with the tool. And things just might get better as I use it.

Community, Plants, Wildlife

Thinning in Winter

michaelmccurryphd

When I start the chainsaw, I attract deer.  The inflow starts with a doe who learned, as a fawn, that my chainsaw meant there would be winter food near the house,  She shows up, with her yearling daughter and two fawns.  She often chooses to browse the mosses and lichens on the trees, as do the rest of her family.  The newer dependents usually just browse the needles – and they seem to come to dinner in their own family groups to minimize conflict.

The place needs thinning.  The large stumps bear witness to the first logging – done around 1910, with smaller stumps showing a second, smaller harvest a little after the second world war.  Yet another scattered group of stumps shows where a man with a horse, a saw and a broadaxe could be in the crosstie business – opportunity, if hard work.  The other stump evidence shows the Christmas tree industry . . . and I wonder if we could have yarded Christmas trees along the old road in the sixties and seventies without the deer browsing destroying them. 

I had a visitor comment, “You’re parking it out.”  I don’t see it that way – nearly 50 years ago, a forester taught me a simple principle – each acre will produce about the same amount of wood.  Spaced properly, the wood grows into harvestable logs.  Additionally, with the open canopy, it will produce about 80% of the grass that would grow on an open meadow.  Forest management pays, but takes a long-term perspective and consistent maintenance.  Others may think I’m parking it out close to the house – I think I’m still that same conservationist . . . though I left that career path almost 40 years ago.

And I learn – doing my thinning mostly in the winter provides food for my semi-domestic dependents.  There is something pleasant about trimming branches on one end of a log while deer browse 15 feet further up.

Apologies to our subscribers if you were notified about this article twice. An unfortunate result of working in the wee morning hours on little caffeine. We’re still only coming out on Tuesdays.