Many people believe a large acorn crop is a predictor of a harsh winter. The truth is, the acorns on the ground today are the prediction of weather conditions two or three years ago.
Bucknell University Professor of Biology Emeritus Warren G. Abrahamson, Ph.D and Executive Director of the Archbold Biological Station (located in Venus, Fla.) James N. Layne, Ph.D worked together on a study of acorn production during the years of 1969-1996 (with the exception of 1991).
The pair observed and recorded the acorn crops of two white oak and three red oak species.
"Jim Layne was really the one who got the project started," said Abrahamson. "He also was the one to make sure the data got collected each year."
The findings of the team may surprise you. In a published report dated September 2003, the research showed that the volume of acorn production each year is partly controlled by external factors like precipitation affecting the acorns during different stages of development during prior years.
Acorn production from bud to completed acorn takes nearly two years for species of the white oak and three years for species of the red/black oak, according to Abrahamson.
In 1989, the oaks in the study were subject to a freeze during the growth cycle. Only one species of oak, the Chapman Oak, was damaged. The damaged trees produced their third highest crop of acorns over the entire 27 year of the study in 1990.
The team reported that they did not experience a complete crop failure of any oak species during the study.
If you've noticed a lot of acorns around your house, Abrahamson who resides in Central Pennsylvania, said the Chestnut Oaks are producing them.
"I have never seen such a large crop in the 30 years I've lived here," he said. "Walking around my property is like walking on marbles."
The rainfall and temperatures in Central Pennsylvania during the springs of 2010-2012 have been favorable for acorn production. The table below list the precipitation and temperature totals for the months of March-May for each of the three years.
|Year||Avg. Precip.||Actual Precip.||Percent of Normal||Temp. Percent Above Norm.|
If favorable weather conditions for acorns mean a bumper crop two or three years later, the crops of 2013-2015 may bring some of the largest crops yet.
"Weather was a very important factor in the study," said Abrahamson. "The production of acorns definitely is not forecasting but hindcasting the weather."
Rain and thunderstorms spreading to the East on Tuesday will put the brakes on the warmup following Easter weekend.
While remaining on a localized level through Tuesday, severe weather will ramp up across the Plains on Wednesday.
Although spring may be in full swing, more than one-third of the Great Lakes remains covered in ice.
A potent area of low pressure moving into the West will dictate the weather from Washington to Texas heading into the new week.
After taking a tumble Easter Sunday, temperatures will quickly rebound in Boston for Patriots' Day.
There hasn't been any measurable precipitation in San Francisco since April 4.
Marquette, MI (1982)
8" of snow fell in Marquette, MI, on this date. This brought the total snowfall to 240" for the winter -- an all-time record.
Southeastern VA (1991)
Torrential rain; 5.89" at Norfolk broke the 24-hour record for April (5.19" set in 1883). This was the most rain in one event since Hurricane Cleo dumped 11.40" from August 31 to September 1, 1964.
Omaha, NE (1992)
Snowfall of 9.3" -- only the 6th time in 100 years that over 1.5" of snow has fallen after April 15th. Only 13.3 inches fell for the entire season before this storm. Other snow totals: Brownsville, NE 14.0" Blair, NE 12.5" Offutt AFB, NE 12.0" Eppley, NE 10.0" Kansas City, MO 2.7"