Wetting hours Aug. 23-30.

There were 49 total wetting hours at our AREC last week, bringing this year's total to 514. This is the lowest total accumulated wetting hours through the end of August since we started keeping track of wetting hours in 1994. The previous low was 521 hr for 1999. Totals for other years, except 1999, since 1994 were all more than 600 hr by now, ranging from 601 in 2005 to 967 in 2000. The total by this time last year was 808 hr.

Fruit maturity

Dave Carbaugh reports that, although the cultivars Ginger Gold, Gala and Honey Crisp matured earlier than normal this year, Red Delicious and Golden Delicious are closer to normal. As of Aug. 24 there was still a lot of starch to convert- a relative rating of 1.7 for Reds and 1.4 for Goldens on a scale of 1-10 where 1 means there is a lot of starch. Soluble solids (sugar) is already on the upswing, 11.5% for Reds and 12.8 for Goldens. Firmness is still good- 18.2 lb for Reds and 18.6 for Goldens. The combination of high starch, good firmness and cooler night-time temperatures for improved fruit coloring bodes well for fresh market cultivars. So, in spite of the earlier bloom date this year, all these criteria are optimistic for a normal progression into harvest and some opportunity to wait for improved color. Last year on the same assessment date, Red Delicious firmness was 17.5 lb, soluble solids 10.2% and starch rating 1.9. Goldens in 2009 were 17.2 lb, soluble solids 12.4% and starch rating 1.7.

Extended wetting Aug 23-24

Extended wetting Aug. 23-24, 16 hr at 67º with 0.8 in. rain. (A pretty good soaker this time).

Wetting hours Aug 16-23

There were 44 total wetting hours last week, bringing this year's total to 465. A significant portion of last week's wetting hour total was from rainfall at relatively warm temperatures (as noted below), increasing the potential for rot development on maturing peach and apple fruits.

Extended wetting Aug. 18-19

Extended wetting Aug. 18-19, 26 hr at 69º with 0.46 in. rain.

Also 13 hr wetting Aug 15-16 at 76º with 0.02 in. rain.

Extended wetting and increased summer disease activity

Extended wetting Aug. 12-13, 21 hr at 73º (0.58 in. rain at our AREC). There were 64 total wetting hours last week, bringing this year's total to 421. Also extended wetting Aug. 15-16 13.5 hr at 76º (0.24 in. rain)
  Of course any rain we get is much needed, but these rains at warm temperatures do increase the potential for summer diseases, especially bitter rot.  Bitter rot has been observed on fruit which had frost cracks, potentially increasing the inoculum level and disease pressure on healthy fruit.

Increased summer disease activity

Extended wetting Aug. 4, 7.5 hr at 76º (with only 0.05 in. rain at our AREC). There were 24 total wetting hours last week, bringing this year's total to 357.
There were several other warm showers last week and a total of 0.41 in. rain. Bitter rot has been observed on fruit which had frost cracks, potentially increasing the inoculum level and disease pressure on healthy fruit.

Wetting hours last week

Extended wetting July 31-Aug. 1, 9.5 hr at 68º (but only 0.04 in. rain at our AREC). There were 20 total wetting hours last week, bringing this year's total to 333.