Thursday, March 28, 2013

The Outside Story: Pasture Pines

weevilThe eastern white pine is the tallest tree in this part of North America, with the biggest specimens getting up near 200 feet. They can live for 250 years or more. A truly big one is jaw-droppingly impressive.

Unfortunately, many never reach their full potential. Dubbed pasture pines, cabbage pines, or wolf trees, these squat multi-stemmed trees look like shrubs on steroids. Not for them the soaring magnificence of a robust, healthy pine. I’ve got plenty of them in the woods in back of my house. When I look at them, I just sigh.  You can blame it all on a native insect: the white pine weevil, Pissodes strobi.

“It’s an opportunist. It’s probably on every acre of pine land that there is,” said Kyle Lombard, forest entomologist with the New Hampshire Division of Forests and Lands, of the weevil. “The thing is it doesn’t kill the tree. It’s not like blister rust in that way. It just ruins its economic value to the landowner.”

The white pine weevil is a drab, nondescript beetle about a quarter of an inch long, with a serious-looking snout. The adults overwinter under trees and emerge in spring to fly or climb to the tops of pines or other trees – they prefer white pine but they’ve been known to damage 20 other species of conifer as well. They lay eggs in holes they cut in the bark just below the leading, topmost shoot. When the eggs hatch, the larvae feed beneath the bark, girdling the shoot, which turns brown and droops, looking like a shepherd’s crook. The larvae pupate beneath the bark in a chip cocoon, emerging as adults in summer.

The tree compensates for the death of the leader by self-selecting a branch, or branches, as the new leader. Normally, the leader produces hormones that keep the lower branches from growing upwards, but when it’s gone, the nearest side branches all turn up, competing with one another for dominance; this results in a forked main stem. Trees that get “weeviled” year after year end up with a multitude of “leaders” and no real trunk. They look like tortured candelabra.

Weevils like a nice, thick, juicy leader on a tree that’s growing where the sun warms it in late April or early May when the females are looking for a good spot to lay their eggs, said Lombard. Trees growing in fields are prime targets. Half a century ago, the area in back of my house was an old field, now it’s a pasture pine party.

With the decline of agriculture in New England, fields were abandoned and reverted to forest. White pines were early colonizers and were weeviled by the zillions. Many of these crippled pines still stand. In fact, it occurs to me that there are people who may not have seen a truly impressive, straight white pine. Instead, they assume that pasture pines are the norm for the species. Sigh.

Even today, if you’re trying to establish a white pine stand in an open field, your seedlings are “pretty much going to get hammered, 100 percent,” said Lombard.

On the other hand, genetics might be on your side, said Lombard. “If the seed source happens to be one of those that produces a thin leader, you won’t see much in the way of damage.” But he said he wouldn’t count on it: the seed sources for white pines in the northeast are from all over the world, and most grow a leader that is “more than suitable for white pine weevil.”

If you can, start your white pines under an overstory of hardwood trees to shade them from that leader-warming sun, said Lombard. This forestry technique, known as shelterwood, was invented for exactly that reason, he said. “All you have to do is keep a lid on the white pines for a while and you’re good to go.”

For ornamental trees planted in the open, pruning infected leaders and burning them is one way to cut down on numbers of the beetles and removing all but the strongest competing branch will help the tree reorient itself.

If, like me, you have a lot of older pasture pines soaking up sun in your woodlot, well, they’re not worth much. Loggers and sawyers shun them, Lombard said. I could have them chipped for biomass. “Then again, lots of people just girdle them with a chainsaw and leave them for the woodpeckers to enjoy,” he said.

Joe Rankin is a forestry writer and beekeeper who lives in central Maine. The illustration for this column was drawn by Adelaide Tyrol. The Outside Story is assigned and edited by Northern Woodlands magazine and sponsored by the Wellborn Ecology Fund of New Hampshire Charitable Foundation:  wellborn@nhcf.org.

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The Adirondack Almanack publishes occasional guest essays from Adirondack residents, visitors, and those with a biding interest in the Adirondack Park.

Submissions should be directed to Almanack editor John Warren at adkalmanack@gmail.com.




7 Responses

  1. Charlie Stehlin says:

    The white pine!My favorite tree.My favorite probably because of the size and age of them,the amount of years it took them to get so big.I measured one in Moose River last September two feet up from the ground at seventeen feet around.Now that may not sound like a lot of feet around but i’m here to say that’s a mighty big tree.A white pine from a distance stands out,but until you get close to them,until you are standing at the base of one,only then can you get a true perspective of their grandiosity.Moose River has a whole bunch of these grand trees which I call remainder trees,the ones that the axe-men missed in the 1800’s. Back then the axe-men were like the politicians of today…no foresight.Fortunately many of these trees were spared,but they are far and few between and you must know where to look for them. I know somebody who bushwhacked the woods to get to the Blue Ridge and he told me there are some mighty giant white pines atop that mountain. In “History Of The Lumber Industry In The State Of New York” by William Fox (1901) “there is a record of a white pine that was cut in the town of Meredith that measured 247 feet in length as it lay on the ground.” They cut them down to use the wood for the mast for ships mainly. Jared Van Wagenen,in his book “The Golden Age Of Homespun” (1953)says, “A good many farms had springs,but the trouble was their distance from house to barn.The crucial problem was some sort of pipe to lead the water.With the resourcefulness that seems to have been a part of the age,he (the pioneer) hit upon the happy plan of taking small logs and boring a hole through them from end to end; they were then joined to make a continuous pipe.The raw material for such pump logs was always available in such abundance that it was almost without price.When it was to be had,the favorite wood was white pine because it was soft and easy to bore,and it was commonly obtainable in small,smooth logs of uniform diameter.” The white pine is such a beautiful tree.Their sight and imposing features from a distance draw me near to them.When i’m in Moose River I always find me one of these massive trees and sit under it for long lengths of time and pay attention to that soothing silence that only comes with those magical woods.

    • Bill Ott says:

      Charlie,

      Mr. Rankin’s article taught me something new about White Pines, but your comment made my day, as this is my favorite also. I found an Almanack article about a White Pine harvest along Rt 28 last September where the largest trees were about 25 to 30 inches in diameter, or less than 8 feet around. (“The white pine plantation at Huntington was planted in 1916.”) I’ve measured several trees along the Oswegatchie at 11 or 12 feet around at chest height, and can only dream of a 17 footer.

      Concerning the Pasture Pine problem, the plantation is to be replanted with White Pine. I wonder what their plans are for this drab nondescript beetle and if their solution is available to the drab nondescript landowner.

      Bill Ott
      Drab Nondescript Lakewood, Ohio

  2. Dave says:

    Down here in the finger lakes I see a lot of white pine “bushes” as described, but up in the Adirondacks, it appears that the beautiful big trees are unharmed by this pest…. Even when viewed from cliffs above, they look really healthy in the crowns. Are the weevils just low-flyers? What is the deal?
    Thanks

  3. Charlie says:

    I can only imagine what this landscape looked like before the white man started hacking away Bill.We’re still hacking away.The 17-footer I mentioned was just one of many in the Moose River woods.I’m sure some are bigger than that.The earth around this tree is raised up so as to make the tree appear as if it is on a mantle.I had to climb a little tio get to its base.This raising is due to the massive roots lifting the earth around it as it has grown undisturbed over the years.From the camp where I stayed,which was on a hill alongside the Moose River,I saw through the clearings in trees many white pines towering over the rest of the forest.They stand out like the steeples of churches stand out.Surely these were virgin trees,or second generation.I cannot wait to get back in those woods….just so I can sit under one of those majestic white pines.

  4. Bill Ott says:

    Charlie,

    Have you ever seen a prop root tree? Well, naturally you have. So could this 17 footer be a prop root tree? Figure it out. This would be neat.

    I ran this around my brain stem six times before deciding to post this.

    Bill Ott
    Lakewood, Ohio

  5. Charlie says:

    Prop root trees are those trees which shoot out roots Bill.I don’t think the white pine fits this category.And yes I have seen them.

    • Bill Ott says:

      Charlie,
      Thankyou for your reply. I realize I was wrong in trying to pin “prop root” to the white pine. I had always thought that term referred to a tree which would, for instance, start on a rock and survive by shooting roots into solid ground, eventually covering the rock. I think I remember seeing more of these in the Smokey Mountains.
      Bill Ott
      Lakewood, Ohio