SW Michigan Fruit Update
September 7, 2004
Weather
Last week was warm and summer like. High temperatures were in the 80s with lows near 70 Soil moisture is good. Several storm fronts with heavy thunderstorms moved through the area last week. Most areas received one to two inches of rain last Wednesday. The forecast for this week is for a return to warm weather on Thursday with highs in the 80s and lows in the 60s. Cooler weather will return on Labor Day with highs in the mid 70s.
Southwest Michigan Growing Degree Day Totals March 1, 2004 through August 29, 2004 |
|||
Location |
GDD 42 |
GDD 45 |
GDD 50 |
3206 |
2768 |
2086 |
|
Bainbridge |
3262 |
2819 |
2135 |
Lawton: |
3283 |
2830 |
2166 |
Hartford |
3071 |
2630 |
1958 |
Grand Junction: |
3312 |
2850 |
2161 |
2875 |
2453 |
1798 |
|
Tree fruit
Warm weather has increased insect activity low. Fruit fly numbers are declining but cherry fruit flies are still common. Japanese beetles numbers increased. Codling moth trap catch and Oriental fruit moth trap catch numbers increased. Damage from these two pests also increased. We expect to see more damage in the upcoming weeks. See the article in last week’s Fruit CAT Alert. Trap catch of redbanded leafroller is up but obliquebanded leafroller trap catch remains low.
Peach harvest is slowing down. Oriental Fruit Moth egg hatch is well underway. Oriental Fruit Moth Biofix was April 29 at 300 GDD 45. We are at 2470 GDD-45 since Biofix and egg hatch began at about 2250 GDD after Biofix. Our trap catch numbers went last week. Increase with the return of warm weather.
In Cherries, another wave of cherry leaf spot defoliation is taking the last of the leaves.
Plum harvest is winding down.
Apple growers are picking Gala, Honeycrisp and Empire. Some Honeycrisp in sandy sites is over mature. Codling moth trap counts spiked sharply Monday indicating a heavy flight late last week. We are in the middle of the second-generation flight and egg hatch. Biofix on May 7 at 235 GDD base 50, we are at 1861 GDD after Biofix. The end of egg hatch is expected at 2100 GDD after biofix. About 250 GDD base 50 are needed from flight to egg hatch, so a lot of eggs will begin to hatch 250 GDD after this surge in the flight. We accumulated about 125 GDD base 50 last week so we are half way there. Warmer weather is forecast to return and treatment of mid and late harvest apples should be made before the end of next week. Be aware of expected harvest dates and PHI when you plan your treatments. Late season Oriental fruit moth may migrate out of the orchards were they are established to nearby plantings. Sprays to control Codling moth should also control Oriental Fruit Moth. Spotted tentiform leafminer and White apple leafhopper are out. Some apple orchards are severely bronzed from European red mite.
In Pears, harvest of Bartletts is finished and harvest of later varieties such as Bosc has begun.
Small fruit
In Blueberries, growers are finishing Elliott, the last variety of the season, and many growers are finished for the season.
Grapes veraison is ending. Color is well developed in most vineyards. Cooler vineyards and those that suffered frost injury and have many secondary fruit clusters still have some green berries. Grape berry moth flight increased last week. Damage is heavy in some vineyards. Growers should be scouting hot spots and the edges of their vineyards for stings and other signs of recent berry moth activity. Grape leafhopper nymphs are spotty, most sites have very few. Phomopsis symptoms are easy to find in most grape vineyards. There is no effective treatment at this late date. Downy mildew is increasing with the heavy dews common in late summer. To see a regional grape scouting report go to http://www.grapes.msu.edu/.
Southwest Michigan Grape Growing Degree Days form April 1, through Sunday August 29, 2004. |
|
Location |
Grape GDD |
2039 |
|
Bainbridge |
2086 |
Lawton: |
2074 |
Hartford |
1911 |
Grand Junction: |
2107 |
1761 |
|
In Strawberries, new growth looks good except where potato leafhoppers have been feeding. Strawberries are setting buds for next years crop and weed killers should not be used at this time.
Fall Raspberry harvest is in full swing. Fruit rots especially gray mold and blue mold are a problem for some growers. Captan is only fair against these diseases. Picnic beetles and ants are attacking over ripe fruit.
