2010 DD Accumulation for Apple Scab Ascospore Maturity

2010 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	East Dorset Bennington Co. Elev. 408 M
Green Tip Date	4/03	4/03	4/04	4/03	4/05
4/04	59	56	27	55
4/10	180	187	141	192	100
4/17	268	2777	230	289	200
4/24	380	392	343	407	299
5/01	489	504	455	531	403
5/08	683	702	644	743	591
5/15	790	808	750	854	684
5/22	980	999	945	1045	860
Date for 900 dd	5/20	5/19	5/21	5/17	5/23

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 2010 New England Tree Fruit Management Guide
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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