2007 DD Accumulation for Apple Scab Ascospore Maturity

2007 Estimated Degree-Day Accumulation (Base 32F, from McIntosh Green Tip) for Selected Sites
	^{UVM HRC ^{South Burlington Chittenden Co.} ^{Elev. 71 M}}	Shoreham Addison Co. Elev. 107 M	South Hero Grand Isle Co. Elev. 54M	Dummerston Windham Co. Elev. 171 M
Date	04/23 (GT)	04/23 (GT)	04/23 (GT)	04/22(GT)
4/28	120	123	120	150
5/05	230	236	231	279
5/12	423	425	426	474
5/19	547	556	550	620
5/27	772	782	778	856
6/02	971	985	974	1061

Degree Day and other weather information received from Skybit E-Weather Service: http://www.skybit.com/

Cumulative Percentage of Ascospores Matured at Various Degree Day Accumulations (Base=32 F)¹
Degree Days (2)	^Cumulative ^Ascospores ^{Matured (%)}	^90% ^{Confidence Interval} ^{for Estimate (3)}
35	1	0-7
¹¹⁰	³	^0-14
145	5	1-19
215	12	2-32
325	25	7-55
450	50	21-80
575	75	46-94
685	90	69-98
740	95	79-99
790	97	86-100
865	99	93-100
1-Table from "Pest Management Recommendations for Commercial Tree-Fruit Production, 2006", Cornell Cooperative Extension Publication.
2- DD should be recorded from the date when 50% McIntosh fruit buds are between silver tip and green tip. The base temperature = 32F. Data of Gadoury and MacHardy, 1982.
3-The width of the 90% confidence interval is a statistical measure of the precision of estimated maturity. It is the range within which the estimate should fall 90% of the time.

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