Monday, April 01, 2013

Ashes to Ashes (and oaks to oaks)

Can something be tragic and inspiring at once?
For me, the ash disaster is.

“Death to the Ash!” means Life to the Oaks (and hundreds 
of other declining species)! Or at least it can...

In many forest preserves, ash trees are the major invasives that have been destroying oak woodland and savanna ecosystems.
Flaky bark means dead ash. These were left to the borers when this savanna was restored.

When scientists 
told us that the emerald ash borer would kill all our big ash trees, it seemed unthinkable. 
We could have waited (sort of like “climate change deniers”)
to see if the scientists were right. 
But instead we stopped cutting big ash as we restored our 
oak savannas and woodlands. 
Why stop? 
There’s urgency here. Thousands of populations of hundreds of species are dying out year after year because of the shade of ash and other quick-growing "weed trees." 
Why waste time?
We now cut buckthorn, box elder, basswood and similar invasives, but we leave the ash. 
can dispatch them.
Educating people to appreciate the evil of invading shade is challenging. Death by ash is different from death by bullet or auto crash. It’s harder for people to understand - or identify with. But whether by
Hundreds of animal and plant species now have a second chance.
shade or by clear-cutting for a mall, you’re equally dead, if you’re a young oak tree. Oaks of all ages love light and need it. Shade is like cancer, a slow and ugly killer.

In the 1800s, when the natural fires stopped, white and green ash from the ravines and floodplains overran our oak woodlands and savannas just as destructively as the other invasives. But now, with ash death, a huge opportunity has opened up for tens of thousands of acres.

Owners of conservation land are making plans to convert the misfortune of the ashes to the fortune of the oaks – and a potentially miraculous recovery of the plants and animals that depend on the open oak ecosystems.  Should I list a few? Gray fox, blue-spotted salamander, creamy wild pea, ruby-throated hummingbird, purple milkweed, and great-spangled fritillary.  

In areas of many ash trees, half the work is now being done for us. Before new light gaps fill with invasives, these areas deserve quick plans and action. What does that mean? Cut other key invasives,
This dismal photo shows a dead bur oak, leaning across the foreground. It died of shade
 from faster-growing ash and basswood, in the absence of fire. Gone with the oaks are 
hundreds of other species. How can we teach people to see this? 
start controlled burns, re-seed if needed, and provide the education and political support that goes with all the above.

We mourn the ash, an important component of many non-oak forests. At the same time – we celebrate the liberation of animals and plants of the oak lands. Huge noble areas that seemed doomed now have a chance to thrive again.

Ashes to ashes

When they die, they’ll stand for years as habitat for beetles and woodpeckers and flying squirrels and great crested flycatchers. Some people will argue to cut them all down. Nature wants them to stand for the decade or more as they have their "second life" as yet another irreplaceable habitat. Someday their weathered trunks will fall. Then a slowly rotting log on the ground is yet a third habitat. That log means salamanders, frogs, snails, beetles, roly-polies, mushrooms, and places for us to sit and contemplate the miracle of lives. Ultimately, beautiful and life-giving burns will consume each log. Ashes to ashes.
Eastern bluebird on scarlet oak branch. These handsome creatures now 
breed again at Somme. Hundreds of less-easy-to-see species also need 
the dappled light of open oaks and now-rare diversity that oaks support.  
(Photo by Lisa Culp)

Oaks to oaks  

When oaks aren’t reproducing their cute little baby oaks, some people imagine we must be seeing a natural process called “succession.” It’s the opposite. When the once light-dappled floor of the oak woodland is clotted with dark invaders, whether ash or buckthorn or maple or whatever – the rich, ancient ecosystem dies. Oaks are the foundation of a community that is the Earth’s only home for thousands of species that don’t live in other kinds of woods. Now rare flycatchers, woodpeckers, mushrooms, nematodes, walking sticks, shrubs, foxgloves, grasses, sedges, ants, lichens, rare and potentially-important bacteria as well as other tree species all depend on our oak woods. Let's rescue them from the oblivion of extinction. Now's the time. Save them!


Daniel Suarez said...

First of all, great title.
Second of all, I wonder about sites that may not have a large abundance of ashes or insects that could take care of aggressive tree species. Would girdling another species, say basswood, still provide the important habitat in its "second life", or are ashes somehow distinct in this regard?
I think this topic is an important one. Many people have to varying degrees restored plant and animal communities, but not much is mentioned in the discussion about insect conservation/restoration. Since we know so little about them, providing as much habitat for them to persevere seems to be an important but possibly overlooked management practice.

Anonymous said...

Will the return of fire to oak woodlands control ash, box elder, maple, and basswood? Was the woodland audit a measure of trees that invaded oak woodlands with or without regular burns? If the return of fire to the ecosystem will also return the equilibrium of native species then wouldn't resources be better focused on non-native invasive species?


Stephen Packard said...

Daniel, I very much agree with your suggestions. Yes, people care about birds, but if conservation doesn't protect the insects they eat, then we don't have a thriving bird community. Old woods and savannas typically have an abundance of dead "snags" that support a great diversity of nesting habitat, insects, fungi, etc. Many "recovering" restoration sites have few old trees. Especially in these areas it would be much better to girdle many trees than to cut them down.

Stephen Packard said...

James, good questions. These days, in my experience, most fires in most woodlands are not intense enough to kill most large "native" invasive trees. Thus, for oak reproduction, invading trees typically need to be thinned out by cutting or girdling. The Woods Audit sampled the average woods of the region. Most of those woods had not been regularly burned. Indeed, many of them have a fuel structure that they would not now burn except in extreme conditions. One purpose of burning is to increase grassy fuel and decrease the woody fuel that makes for burns intense enough to kill typical big trees.

Anonymous said...

At Deer Grove they have been able to get fires that were plenty hot in oak woodlands heavily invaded by Maple and Basswood. The reason for their success was they had removed the buckthorn which holds its leaves late into fall. The buckthorn shades the leaf layer during prime burn season preventing the sun from drying out the fuel. I do not think the woodland grasses, sedges, and rushes contribute much to fuel compared to the dried deciduous tree leaves. These graminoids are either too spare or are still green when a burn occurs. It does not seem that oak leaves burn significantly hotter than maple or basswood.

It is true that a hot woodland burn will not kill large trees. Seedlings and saplings of fire intolerant species are killed. Maple trees are constantly having their bark stripped off by squirrels during the winter. Other tree species regularly die from any number of factors. This is actually an argument to have a diverse assemblage of trees in woodlands. If recruitment of fire intolerant tree species was prevented by correctly prescribed burns then these species would slowly disappear by attrition.

Savannahs are a different case altogether. Fires on the prairie edge are hot enough to kill large trees. It would be wise for any land manager trying to create a prairie/savannah/woodland dynamic to start thinning on the western edge of their property. There is more to prairie/savannah/woodland than just fire intensity. Unobstructed drying winds from the west are also important.

I have seen prescribed burns which destroyed thousands of sprouting acorns. It seems burning during the spring after a bumper acorn crop is counterproductive if your objective is to increase the recruitment of given species of oak. This is something that needs to be given more consideration by those prescribing burns.

I hope some of these thoughts are helpful.


Anonymous said...

Awesome blog...lifted my hope! I saw my first walking stick in IL last summer on a geranium planter at Temple Jeremiah in Northfield. I had not seen one since I left the Pine Barrens of New Jersey where I saw them all the time in my back yard. Thanks to your blog, my blue bird house is complete and ready for the yard! Would like to talk sometime as to what plants are native to the floodplain forests and where their growth should be limited. John Cherry

Rob Liva said...

Great perspective. The loss of the ash tree should be viewed as an opportunity and call to action.