Can trees migrate?

Really, do trees migrate? The answer is a yes. A little clarification here, though; trees don’t actually move themselves. What does occur: tree populations can shift over time. A recent study confirms that, over the past three decades, trees in the eastern United States are shifting their population centers west and north. Several tree species common in the east, such as white oak, sugar maples, and American hollies, have shifted their population center west since 1980. The study also shows that more than half of the species studied also moved populations centers northward during the same time period.

So, what the heck is going on? you may ask. The science team has a hypothesis: Climate change has increased temperatures across the eastern United States; it has also altered rainfall totals. The Northeast has received a bit more rain since 1980 than it did during the past century. Meanwhile, the Southeast has gotten a bit less rain. Meanwhile, the Great Plains, with emphasis on Oklahoma and Kansas, get much more rain than historically normal.

“Different species are responding to climate change differently. Most of the broad leaf species — deciduous trees — are following moisture moving westward. The evergreen trees — the needle trees — are primarily moving northward,” according to one author of the study from Purdue University.

There are potentially many forces and factors at work, as well — from land use changes, wildfire frequency and various types of pests and blights. Still, the scientists argue that at least 20 percent of the change in population area is driven by changes in precipitation caused by climate change. If you would like to read the study, it’s available on the web at science.advancesmag.org and entitled “Divergence of species responses to climate change.”

Well, how has our local weather (not climate) been this past month of May? It appears that we are starting to see “normal” precipitation patterns again. Here at the home weather station we got 1.71 inches of rainfall, or 0.61 inches above the mean rainfall, for May at 1.10 inches. Should note that so far this calendar year we’ve received 9.52 inches of precipitation here at my home weather station. Again, we average 10.55 inches annually. An above-average year for precipitation is fast approaching. We had a high temperature of 90.7˚F (all-time high was 100˚F in 1986) on the 29th and a low of 34.0˚F (all-time low of 21˚F in 2002) on the 14th. The Climate Prediction Center says for the next three months there is a 30-percent chance of above-normal temperatures, while precipitation has an equal chance of being above or below normal.

Looking skyward during the month of June, our friends at EarthSky share this with us: “Three of the five bright planets are easy to see in June 2017: Jupiter, Saturn and Venus. Jupiter appears first thing at dusk and stays out until well after midnight. Saturn rises at dusk or nightfall and stays out for the rest of the night. Venus rises before the sun and reaches its greatest elongation — its farthest point from the sun on our sky’s dome — on June 3rd. Mars and Mercury will be hard to spot this month.”