Thomas G. Chastain

One of the most often heard comments (or complaints) so far this spring has been about how cold and wet it has been.  Has this spring’s weather been as cold and wet as it seems?  The answer is yes!  Compared to the long term averages for Corvallis, April temperatures would have been roughly normal for the month of March (Fig 1 – click on figure to enlarge).  But it does not stop there as May was only a bit warmer than the average April.  Moreover, this year’s spring weather is part of a trend.  The past four springs have been colder than normal (2007-08 crop year data not shown).

The 2011 spring season has also been wetter than the long-term norms for Corvallis (Fig 2).  Last spring was also wetter than normal as well, but 2009 (2008-09 crop year) with the exception of a very wet May.  The long-term trend though has been toward wetter springs, especially since the 1960s.  Overall, precipitation at Corvallis has increased by about 3 inches during the past 120 years with most of that increase occurring in the spring.

Colder, wetter springs delay crop development as well as the timing of field operations.  Some pests such as rusts in grass seed crops may be lessened under these conditions but the incidence and severity of other might increase.  These trends and their potential implications for seed production bear watching.