For instance, about the time that the Northern Lights forsythia is in full bloom (94 GDD), the eastern tent caterpillar has hatched (92 GDD). Another common insect problem, the European pine sawfly hatches (144 GDD) about the time that the Bradford callery pear first starts blooming (142 GDD).
For someone wanting to control a pest, it’s a lot easier watching the trees that correlate to emergence of the insect than it is hunting for the insect itself.
Last Friday we were at 31 GDD for Springfield, Ohio, zip code 45502. On Feb. 21 we were at 45 GDD. Silver maples should be in bloom at 42 GDD and red maples bloom at 44 GDD.
If the weather stays warm and we continue to accumulate GDDs, we will see Northern Lights forsythia blooming at 58 GDD.
Looking over past years in terms of plant development, on this date, February 21st, we were at the following GDDs: 2010 - 0; 2011 - 11; 2012 - 12; 2013 - 23; 2014 - 4; 2015 - 4; 2016 - 22; and 2017 - 45.
Going back 10 years, I found that we were at 44 GDD on this date in 2009 and 34 in 2008.
To some this is boring information but I find it fascinating. If you want to learn more about GDD and to check out the GDDs for your zip code, go to: go.osu.edu/growingdegreedays
The website is a great tool for plant and insect development as well as for timing of any pesticide applications that you might make.
People are a little concerned about plant development and injury from cold right now and we may see some injury. The key component is in the transition phase from warm temperatures to cold temperatures.
If we have a prolonged warm spell followed by a dramatic drop in temperatures, plant tissues will be tender and likely damaged.