WEATHER

High winds, accompanied by highly variable rainfall, hit NW Michigan on Monday evening. Evaporation rates were quite high this past week at 1.95". June evaporation has totaled 6.13". Rainfall this week at the NWMHRS was 0.57" (including the 0.48' Monday evening). June rainfall totaled 2.96", with 2.06" falling in the first 10 days of the month.

GDD 50: 657; GDD 42: 1139
(Two days behind last year's DD Base 42, and one day behind last year's DD Base 50)

GROWTH STAGES
Apricot: Harcot – 29mm
Plum: Stanley – 22mm
Apple: Red Delicious - 38mm
Sweet Cherry: Napoleon – 19mm
Tart Cherry: Montmorency – 19mm
Grapes: Buckshot berries 

COMMODITY/PEST REPORT

Apple growers who have young plantings should check for and remove fire blight strikes while the cool weather lasts. Blocks with many strikes should be left alone and cankers cut out in a dormant pruning. Codling moth flight is down, as they are between generations. European red mites and two spotted spider mites are up but remain low overall. Potato leafhoppers remain high. Young orchards, even if sprayed two weeks ago, may need re-treating.

Sweet cherry harvest is beginning for a few early varieties. Ethephon is being applied on some tart cherry blocks. Tart cherry growers who are finding leaf spot in their orchards should tighten up their spray schedules and increase rates if they have been cutting back. Post harvest Bravo applications will be very important immediately after harvest. Brown rot is showing up now in unsprayed sweet cherry blocks. Cherry fruit fly adults continue to emerge and have been reported in many commercial orchards, with heavy pressure in a few blocks. Growers who diverted fruit last year and left the fruit in the orchard for some time after harvest could have high numbers of adults emerging directly in the orchard. Two spotted mites are increasing, but they still remain quite low in numbers.

In plums two spotted spider mites are low, but growers should check their populations before cherry harvest begins. Vendex is the only option for controlling mites in plums and should be applied if you are somewhere between 5 and 10 mites per leaf.
 

MISCELLANEOUS

Phytotoxicity On Tart Cherries
By Jim Nugent, District Horticulturist, MSU-E

Due to a recent phytotoxicity problem related to spray injury observed on tart cherries, we tried a few combinations of materials in an unreplicated trial at the NWMHRS, applied under similar conditions and at the same rates. 

Applications were made in the morning at temperatures of approximately 74 degrees F on a day when the temperature rose to a high of 83 degrees, followed by a high of 87 degrees the next day. The results were as follows:

CIAB to Meet
By Jim Nugent

The CIAB will meet tonight, Tuesday, June 29^th, beginning at 7 p.m. at the NWMHRS. Based on the USDA crop estimate of 260 million lbs., there will not be the need for a diversion in 1999. If the crop picks out above approximately 288 million lbs., however, then a diversion will be established. More details will be available at the meeting.

Wanted: Volunteers for Orchard Study
By Jim Nugent

Last week we announced that the NWMHRS is planning to study nutrient levels in soils in older orchards this summer. The purpose of the study is to ascertain the potential value of precision applications of fertilizers. The study will be run in cherry and apple orchards of at least 5 acres in size and 15-30 years of age in the 5 county area of NW Michigan. We want one or two blocks per grower in a total of about 20 orchards. Blocks will be mapped and sampled in sub-units based on soils and tree growth to assess nutrient variability. Participants will be provided with the results. We are still looking for volunteers, particularly in counties other than Leelanau. Growers interested in participating may do so by calling 231/946-1510.
 

NW Michigan Horticultural Research Station
Insect Trap Count Averages - 1999 
 

DATE	Codling Moth	Spotted Tentiform Leaf Miner	Lesser Peach Tree Borer	Greater Peach Tree Borer	American Plum Borer	Oblique Banded Leafroller	Grape Berry Moth	Dogwood Borer
5/18	0	660	8		30
5/24	0	88	1.3		14.3	0
6/1	.6	85	17		4.6	0	9
6/8	2	15	17.3		2.7	0	7.7
6/14	1	342	11	6	.3	7	4.3
6/21	.33	511	10	5	0	2.3	1
6/28	.75	455	6.3	1.6	.75	2.3	16.3	10.6

 

Please send any comments or suggestions regarding this site to: 
Bill Klein, kleinw@pilot.msu.edu

Last Revised:6-30-99