Balance of nature: Oaks and acorns (Introduction)

by David Turell , Saturday, November 05, 2016, 22:55 (2730 days ago) @ David Turell

Lots of animals like to eat acorns. This is a problem for oaks who want to continue reproducing but the whole problem is bound up in a balance of nature which involves lice, mice, and gypsy moths, along with variable acorn production:

http://www.wsj.com/articles/boom-or-bust-breeding-cycle-that-helps-the-mighty-oak-survi...

"At unpredictable intervals, groups of stately oaks, usually recognized for their strength and longevity, breed like rabbits. The phenomenon is known as masting, or the simultaneous production of unusually large numbers of acorns by a population of trees.

"It’s impossible to anticipate a mast year because scientists aren’t sure what triggers it, and few places collect the data necessary to verify when it occurs, but this year, oak trees on Long Island and some species in central Pennsylvania are dropping acorns like there’s no tomorrow.

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"The bumper crops are beneficial because they increase the likelihood that a few oak seedlings will reach maturity. But other consequences ripple through the ecosystem. Animals that feed on acorns will feast on the bounty, and their populations, normally controlled by limited food supplies, will swell. The parasites they support will do the same.

"One important beneficiary is the white-footed mouse, the main reservoir of the bacterium that causes Lyme disease.

"About 10 months after acorns peak in October of a mast year, large numbers of sated mice will begin hosting tick larvae, and about 10 months after that—in May or June the second year after the mast—those larvae will develop into nymphs, which can bite people.

"While deer are often associated with ticks that carry Lyme disease, the ruminants don’t transmit the infection. Mice do, and when they flourish, the disease will proliferate.

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"Last year, New York’s Hudson Valley experienced a mast year, according to Dr. Ostfeld, who has been counting acorns on the institute’s 2,000-acre property since 1992, and this year it was overrun by what he described as a mouse plague. He expects the coming year to be “risky” for Lyme disease, but on the plus side, the mice will also chow down on the pupae of gypsy moths, which defoliate trees and are one of the country’s most devastating forest pests.

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"Producing acorns takes a lot of energy, they say, and after a large crop, it’s possible that the trees, which grow slowly in mast years, must redirect their resources to support new growth. They and other scientists also hypothesize that boom-or-bust cycles are adaptations that help oaks outmaneuver predators that gobble up their yield in meager years.

“'What the oak is trying to do is produce so many acorns that predators like chipmunks, squirrels, deer and birds can eat all the acorns they want, but the tree has produced so many there will be leftovers to produce seedlings,” Dr. Abrams said.

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"Areas that kept out deer and thinned the understory to make room for seedlings improved survival to 56%, but the oaks’ struggle to regenerate was apparent.
“In years when we don’t get bumper crops, most of the acorns are consumed or destroyed,” said David R. Jackson, a forest resources educator with Penn State Extension.

"Increases in the population of deer, which eat both acorns and seedlings, and a century-old forestry policy to eliminate fires that, historically, benefited oaks, make mast years even more important for regeneration."

Comment: Look at the diagram on the website. Note the interacting complexity of this ecosystem as a great example of the importance of the balance of nature. Everyone gets to eat. This system involves two insects, oak trees, changing environmental stresses, mice, deer, human varying forestry practice activities, all related to a varying supply of acorns. God's activity is primarily in the production of a bush of life, which then allows for many interactions between all the organisms that can be involved as part of the network.