Depending on where you are in the United States, you might have noticed the warmer temperatures this year. The first day of Spring was March 20, 2023. But, according to Harry Stevens from The Washington Post, nature does not know what month of the calendar we are in but instead responds to the gradual accumulation of heat at the beginning of each year. When the daily average temperatures rise above freezing, this sends a signal to the plants and animals that life is again preparing to grow. On average this year, phenology stages of bud break were the earliest it has been in 40 years!
According to the map in Harry’s article, leaves have sprouted early in the Eastern half of the country, this is most likely due to the high atmospheric pressure that warmed the East this winter. The Western side of the country experienced a low-pressure system which kept conditions cooler and wetter, this in turn had leaves arriving late in the Southwest and about right on time in central California.
The important part to keep in mind is that this type of weather generates cascading effects for plant and wildlife species. For example, Texas wintergrass will green up much earlier and may potentially go dormant faster. Warm season grasses may also follow a similar pattern leaving a break in forage production earlier in the year typical of drought conditions. Pricklypear may put on fruit and pads much earlier. Mesquite may be variable in phenology stages creating havoc for foliar herbicide applications and Live Oak trees may be vulnerable to any pricklypear applications because of the early leaf shed and new growth.
According to Mark Schwartz, a climatologist at the University of Wisconsin in any given year, the timing of Spring has to do more with the seasonal variation with more frequent cases of earlier Springs.
Curious to see if you are going to have a late or early spring? Check out the interactive map.
For more information, be sure to check out the full article.