Freeze damage to peach crop seen in south central Pennsylvania

Weather stations at the Fruit Research and Extension Center in Adams County, Pennsylvania, showed that there was a strong temperature inversion about 5 a.m. with calm winds. The temperature at 837 feet elevation above sea level was 31° F, while at 810 feet elevation, it was 28° F. At 730 ft. elevation, we recorded 25° F on a second weather station.

The differences in air temperature caused by the inversion resulted in a wide range of crop damage estimates. Melanie Schupp examined between 120 and 160 fruits and recorded the elevation of several blocks. Fruitlet death was evident by the browning of the ovules.

The table shows that peaches at higher elevation had almost no injury, while those at elevations below 800 ft sustained significant damage. This was especially noteworthy in the Redhaven block which is situated on the side of a hill. At the top (828 ft) there was no damage, while 67% were dead just 9 rows down at 795 ft.

Growers are advised to cut some fruits and check for dark centers, paying attention to elevation. If damage is noted you should alert your crop insurance adjuster.

Table 1. Effect of site elevation on mortality of peaches at Penn State Fruit Research and Extension Center, April 17, 2020.

	Red Haven	Red Haven	John Boy	Sweet ‘N Up	Coral Star	Messina	Crest Haven	Starfire
Elevation (feet)	795	828	731	731	741	820	820	820
% Damaged	67%	0%	97%	98%	100%	0.10%	1%	0.10%