2022 Seasonal Observations

Ordinarily I just keep mental notes about the weather, but now as the number of trees we care for increases, I think it’s wise to start writing those observations down.

These observations are an important element of caretaking of trees. Knowing local anomalies and trends are useful to determining some of the needs of our trees here in southeast Michigan. These environmental conditions can sometimes explain visual changes in your tree, such as drought stress or fungal diseases.

So here is a highlight note from each season here in the Metro for 2022:

Winter

All things considered, winter was also fairly dry. Snow stayed around for January and February, but didn’t really reappear for long periods between March and April.

The lack of snow covering the ground can result in some interesting things for trees, particularly from the soil. Consistent snow coverage for the winter season insulates the soil, keeping it at a constant temperature. In addition to keeping soils extremely cold, exposed soil will also dry-out more quickly, nor will they be rehydrated in spring as snowmelt.

Trees are more likely to start the year in drought-like conditions when soil snow coverage is inconsistent or absent. Such was the case for our trees here.

Spring

A late frost damaged some of the early blooming trees like silver maple and magnolia, causing a premature loss of blooms this year. This cold zap seemed to delay the leafing-out of silver maples, while also causing some of them to absize a high number of small twigs.

According to the Drought Monitor, our total rainfall this spring was below average rainfall for past springs. Despite that, prolonged periods of high humidity without interruption provided a good environment for foliar fungal infections to take place. This year we saw a high number of foliar fungal infections of many ornamental trees like juniper, crabapple, and pear.

Summer

Much like spring, we were also in a moderate drought during the summer. While we did have acute rain downpours and windy thunderstorms, this type of precipitation isn’t adequate for wetting soils to water trees. Instead, most of it runs off.

We saw a number of cases of verticillium wilt on tree species that we don’t ordinarily see it on. We found infected magnolia, catalpa, and burning bush, among some others.

Autumn

Autumn rain was adequate for proper soil wetting for trees; the rain periods were slow and steady, in contrast with summer’s downpours with lots of runoff.

It is common for oaks and beech to hang onto their leaves while other trees are bare, but it is very abnormal for maples to do that. This autumn there were a noticeable number of maples hanging onto their leaves well beyond frost. Some even have their leaves on today, December 17th. I wonder if this has anything to do with the buds freezing off in spring. And I wonder why this is happening.

A Common Theme

It seems like water, in excess or deficit, was the prevailing cause for what we saw throughout the year. Any kind of water stress can have long lasting effects on trees. Water is more important to trees than even their macronutrients. It is the single most limiting factor in tree growth and tree health.

I wonder if all of these highlight observations combine into something we’ll see next year.

Future newsletter emails will include local and regional topics such as these. Some ideas we have currently are weather advisories, etiquette when dealing with neighbors and trees, and other actionable advice.

If you have recommendations or suggestions we’d love to hear them!