Received for publication September 2, 1969. Approved by the Director of the New York State Agricultural Experiment Station for publication as Journal Article No. 1725.
Present address: Michigan State University, East Lansing.
Present address: Agricultural Experiment Station, Central College of Agriculture, Warsaw, Poland.
Present address: Puerto Real 5, Grenada, Spain.
We thank Amchem Products, Inc., for the gift of Ethrel, Dr. L. R. Mattick and Mr. R. M. Butts for the use of a gas chromatograph and for assistance in its operation, and Miss Joanne Whitcombe for operation of the Hunter Color Difference Meter.