Part 2: Effects of climate on plants
Last time, I talked about how climate disaster has changed how trees are able to sustain life within their own growing zones. For hundreds or even thousands of years, the climate may have been stable enough for the plants to not only survive where they are, but to change their cells to optimize their space. While that was occurring, the insects, birds and animals they depend on to pollinate and disperse them may also have changed to optimize reproduction. So, true niches have occurred, where plants can fend off natural predators and diseases.
The only real exceptions have been when travellers or colonizers of the land have brought non-native plant and animal species aboard their ships, throwing the balance of the ecosystem off.
So now we talk about local changes to trees and shrubs with regard to rapidly changing temperatures, UV rays, winds, and precipitation. Without going too much into the sciences, which may bore you too much (and I really don’t want to do that!), let’s just stick with what you can observe in your natural habitat.
You may have noticed that some trees flower early, as soon as temperatures are just right. Don’t worry if you see trees that look dead long after many other trees have finished their reproductive cycle and leaf out later. They may actually have an advantage, because they can avoid winter and spring temperature fluctuations that may cause frost damage, mould, or pest infestations.
But the trees that flower early can be devastated by a late frost, and when flowering occurs MUCH too early, the tree isn’t ready enough to bring all of its energy into growing the reproductive parts. Remember, it takes quite a bit of energy for the tree to squeeze out those bits. To produce twice in a season may not be feasible for most woody species. A whole year will have to pass before another opportunity occurs, and for species that are already at risk, this could cause extirpation. Because remember too, the step after procreation is leafing out to grow the tree for health and sustenance.
Sap runs earlier in the spring (or late winter) with climate disaster, and this can attract insect pests. They are drawn to the sweetness of the sap as well as the other insects that might gather. For example, ants will gather when mites are nearby. Mites will gather to collect the sap. Ants collect mites to “milk” them. This activity can also attract birds that will not only eat the ants, but may whittle holes in the trees to eat insects that are burrowing inside the bark. Bark insects come out of hibernation earlier when warm weather hits too early. There are many insect/bird/animal cycles that can be affected when unseasonably warm weather hits.
Something else happens when weather turns too warm, too soon. In northern areas like mine, and in higher elevations like the Rockies, snow is essential. It provides enough water for plants when they are first blooming, flowering, budding, and causing sap to flow. It melts slowly under normal circumstances, providing a steady source of moisture in the ground and in the air as temperatures rise. In addition, if snow is deep near trees, it can prevent frost damage to trees. When trees feel warmth on their bark, they begin to awaken from dormancy. The cells begin to function. New growth in bark and branches begins, as well as the aforementioned functions.
After cells leave dormancy, risk of frost becomes a huge issue. This new growth can be damaged when cold hits. The tissues in these growing parts get injured, just like when you get frostbite. The tree loses those cells which help carry sap or grow new parts. When wounds appear on the tree, pests invade and the ultimate health of the tree suffers over time.
You can see how local trees, individually or in a collective like a forest, can suffer as a result of climate disaster. So again, what can you do to help, besides Reuse, Reduce, Refurbish, Recycle? If you need to prune trees, make sure you are doing so as safely as possible. This also applies if you decide to tap trees for syrup. Wash your tools before using them and immediately after finishing each tree. Don’t carry diseases from one tree to another. If you are camping or looking for firewood, burn only what you find local to your fire. Carrying wood over distances can also provide transportation for insects like the ash borer to migrate farther than their normal range. And when they find a new location that is hospitable because humans have graciously warmed it for them by polluting, they will bore through new trees and keep on truckin’.
Maintain healthy trees, leave dead trees (when safe to do so) for wildlife, and ask for help from qualified people in the fields of forestry, horticulture, landscaping, biology, phenology, and similar disciplines.