Sizzling Spring Temperatures Disrupt Plants, Destroys Food
A couple weeks ago my high school history teacher emailed and asked if I'd been watching the searing temperatures along the Midwest, Northern Plains and into the Northeast. Not only had I been watching them, but also I made a rather eerie prediction about our trees and critters, which unfortunately in part seems to have been correct.
Plants in the Northern hemisphere require an accumulated amount of heat in their protective buds in order to commence growth in the springtime. In plant physiology parlance we call this a 'heat sum' and the exact heat sum is well-documented for every species and in particular our food crops like apples, peaches, apricots, cherries, pears, cranberries, blueberries, strawberries, etc.
Temperatures in mid-March (2012) across the Midwest up into the Northern Plains and across into the Northeast were record-breaking, eclipsing anything we have seen since the inception of continuous record keeping in the late 1880s.
Once plants receive their required heat sum, they break dormancy begin to flower and require (mostly) bees to assist them with pollination. In New Hampshire plants have commenced this process as much as five weeks ahead of time and in Indiana, four weeks earlier than normal. This precocious spring growth has exposed plants to late spring frosts, which have recently smothered Wisconsin, New Hampshire, Michigan, New York, Pennsylvania, Indiana and many other states.
Freezing temperatures are lethal to new growth and especially delicate flowers. These exposed parts of new spring plant growth have not evolved to contend with freezing temperatures.
Moreover, in February and early March (2012) more than three quarters of all the honeybees in the U.S. were congregated in central California for the almond pollination; the largest pollination effort on the globe.
Spring temperatures occurred so early this year that many of the northeast beekeepers were not even able to get their hives home from California to pollinate the apples, apricots, peaches and blueberries.
Over the next week the extent of the hard frosts and ruined crops will be determined. New York's fruit trees and grapes are worth alone $700 million. In 2010, Indiana grew over 26 million pounds of apples and Michigan, the nations third largest apple producer, brought to market an astounding 590 million pounds. If there is significant losses, whatever produce makes it to grocery stores, will likely be more expensive than usual.
In the meantime, across the West an unseasonably warm winter has brought migrating pollinators like broad-tailed hummingbirds from Mexico back to Colorado too late as many plants have already flowered. Less nectar for pollinators means less wild flowers get pollinated which translates into fewer seeds being created.
In Washington, D.C. the National Cherry Blossom Festival, which is celebrating its centennial, has begun three days earlier than last year and the peak bloom is now March 20-23 compared to the 100-year average of April 4.
For those of us who live across the West the warm winter of 2011-2012 has spelled some harsh news for conifers. The insatiable mountain pine beetles now appear to be producing two insect generations a year instead of one. The epic feeding frenzy, which has killed billions of mature trees, will continue with no end in the foreseeable future.
Nature is vividly showing us the unintended consequences of what spewing 82 million metric tons of greenhouse gases daily into our atmosphere: Climate disruption. Clearly, the lawmakers need to set aside their differences and once and for all address global warming. America's leadership is requisite to create a low-carbon economy -- a model for China, India and Russia to follow.
Dr. Reese Halter is an award-winning science communicator: voice for ecology and distinguished conservation biologist at California Lutheran University. His latest books are "The Incomparable Honeybee" and "The Insatiable Bark Beetle."
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