Spring-Like Conditions and a Predicted Egg Hatch of Eastern Tent Caterpillars.

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Today's predicted high temperature for Cincinnati is 75 - 77F.  Unfortunately, we may be paying the piper with strong to severe spring-like thunderstorms predicted for this evening.  Cincinnati experienced 21 days with above average high temperatures in January.  Thus far, 18 days in February have had above average high temperatures.



Bumble Bee on Kobus Magnolia


Kobus magnolias (Magnolia Kobus) have reached full bloom in the Mt. Airy Forest Arboretum and Spring Grove Cemetery and Arboretum with bumble bees visiting the flowers.  Cornelian cherry dogwood (Cornus mas) are at full bloom in multiple locations in Greater Cincinnati.  Red maples (Acer rubrum) range from full bloom to blooms opening.  Flower buds on Forsythia spp. are showing yellow with a few blooms appearing.  Callery pears (Pyrus calleryana) look like blooms will appear with only a small additional heat nudge.  Male flowers on English yew (Taxus baccata) are releasing pollen.


Cornelian Cherry Bloom


Red Maple Bloom


Forsythia Bloom Buds


Callery Pear Blooms


Taxus baccata male flowers


I checked the dates on past images of some of the above flowering events and while not scientific, this anecdotal observation paints a strange picture.  The Cornelian cherry dogwood shown at full bloom in the above image (Mt. Airy Forest) was at full bloom on April 1, 2015 and on March 21, 2016.  The red maple (Spring Grove) with blooms opening shown above was at full bloom on March 20, 2009; March 27, 2010; and March 26, 2014.


These phenological indicators coupled with an accumulated GDD (Growing Degree Days) of 95 for the Spring Grove zip code (The Ohio State Phenology Calendar; hot link below) indicate that the overwintered eggs of Eastern Tent Caterpillar (Malacosoma americanum) should be hatching.  I have not yet observed egg hatch because I haven't been looking; such an early egg hatch would be highly unusual.  The earliest I've ever observed egg hatch in Greater Cincinnati was on March 16 in 2012.


ETC 1st Instar Caterpillars


Temperatures are forecast to fall tomorrow to a high of 43F and a low of 25F.  Sunday's temperatures are predicted to reach 49F for a high and 37F for a low.  However, the extended forecast predicts that temperatures will rebound to above average ranges over the following seven days.  What does this roller coaster temperature ride mean for insects as well as plants?  We do not know because we're navigating unfamiliar territory.  However, it's very important to make and record observations now so we can learn more about the short term and long term impacts of our highly unusual spring-like winter conditions.  I would welcome your observations; just click on my name above for my e-mail address.