2001 DD Accumulation for Apple Scab Ascospore Maturity

2001 Estimated Degree-Day Accumulation (Base 32F, from McIntosh Green Tip) for Selected Sites
	^{UVM Hort.Res.Center South Burlington Chittenden Co. Elev. 71 M}	Shoreham Addison Co. Elev. 107 M	South Hero Grand Isle Co. Elev. 54M	East Dorset Bennington Co. Elev. 408 M	Dummerston Windham Co. Elev. 171 M	Franklin Franklin Co. Elev. 137 M
Green Tip Date	04/23	04/23	04/23	04/30	04/21	04/28
04/26	81	87	80	-	145	-
04/29	119	126	119	-	187	-
05/05	296	302	299	169	372	195
05/06	312	319	315	184	389	210
05/12	478	481	482	330	549	372
05/19	624	624	630	461	696	516
05/23	737	736	743	562	801	628
05/27	853	846	862	656	902	746
06/02	979	974	987	771	1033	865
06/09	1171	1166	1182	946	1226	1065

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, 1999", 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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