Fruit Pest Message
April 29, 2010
Hello Connecticut Fruit Growers,
This week apples are in various stages of bloom depending on variety and location in the state. Pears are at or near petal fall. Peaches at petal fall to shuck split. Blueberries are in bloom and strawberries that were under row cover are also blooming. The flower clusters of non-covered strawberries are still pretty tight in the crown. It’s been a cool and rainy week. Growers were busy with frost protection (especially strawberry growers) for the past two nights. Temperatures dropped to the mid-20’s in some locations.
This message includes information on:
Apple Diseases- Apple scab infections occurred this week (April 25-27) at the sites where my weather stations are located (see more below). I also found beautiful! galls of cedar apple rust this week on cedar trees. Hopefully your apple trees had received a protective fungicide prior to the rain for both of these diseases. So far, it has been too cold for fire blight infections during bloom. That can change if it gets warmer and wet later in the bloom cycle, particularly if your orchard has had fire blight in past years.
Apple Scab Update- I have 3 weather stations that are located in Southington, Woodstock and Gales Ferry. See below for the date that data was last downloaded, dates when apple scab infections occurred, percent spore maturity and degree days for apple scab development. The degree days for apple scab spore maturity are calculated with a base of 32 degrees F and start at 50% McIntosh green tip.
The “accelerated” phase of apple scab occurs between approximately 300 to 700 degree days (DD). This is the time when most of the apple scab spores mature; therefore; the critical time for apple scab fungicide treatments. We are still in this “accelerated” phase in the two cooler locations (Gales Ferry, Woodstock). The next wetting event will likely result in a significant spore discharge. Warmer locations (similar to Southington) are in the “final phase”. By the final phase, 95% of the scab ascospores have matured and have been discharged.
Apple scab infection events are calculated beginning with 0.01 inch of rain. Two successive wetting periods are considered a single, uninterrupted wetting period if the intervening period is less than 24 hours.
Southington – April 29 – Apples full to late bloom
Green tip date: March 25
Spore maturity as of April 29: 62%
Apple Scab Degree Days as of April 29: 511
Apple scab infections:
Note: The leaf wetness sensor was not working until April 1, so any earlier infections were not computed.
Gales Ferry – April 28- Apples in full bloom
Green tip date: March 23
Spore maturity as of April 28: 86%
Apple Scab Degree Days as of April 28: 657
Apple scab infections:
Woodstock- April 28- Apples in early to full bloom
Green tip date: March 31
Spore maturity as of April 28: 73%
Apple Scab Degree Days as of April 28: 571
Apple scab infections:
Apple Scab Summary: There were apple scab infections in various parts of the state on March 23, March 29, April 9, April 16-18 and April 25-27. Cooler locations are still in the “accelerated phase”, the peak time of spore maturity. Warmer locations (similar to Southington) are in the “final phase” of spore development.
Thank you to Karabin Orchards, Woodstock Orchards and Holmberg Orchards for helping with data collection.
Mating Disruption for Greater Peachtree Borers/Lesser Peachtree Borers in Stone Fruit – Use Isomate PTB-Dual pheromone dispensers for both species of borers. Place pheromone “ties” in stone fruit trees by shuck split before moth flight begins. Pruning should be done before hanging dispensers (so you don’t accidentally cut them off). The standard rate of PTB-Dual is 150/acre. Use a higher rate (200-250/A) for outside edges of border blocks; areas that haven’t been disrupted before and have high populations; and in blocks smaller than 5 acres. Most peach blocks in Connecticut are less than 5 acres, so you will need to use at least 200 pheromone ties per acre. Note: The mating disruption dispensers should be available from the person/company where you normally purchase your pesticides.
If using the mating disruption lures, you should also hang pheromone traps for each borer species. Use at least 1 traps per block for each species. Hang lesser peachtree borer by petal fall. Hang greater peachtree borer during first week of June. These are used to track adult flight. If mating disruption is used, there should be trap “shut-down” which means no moths should be captured in the traps in mating disrupted blocks.
Critical Temperatures – With the cold temperatures this week, many people are asking about the critical temperatures for both tree fruit and small fruit bud and blossom stages. See this link for the chart:
http://www.canr.msu.edu/vanburen/crtmptxt.htm
Also see Frost Protection: Tips and Techniques (for strawberries and blueberries):
http://www.fruit.cornell.edu/Berries/genprodpdf/frost%20protection%20tips%20techniques.pdf
Errors in Table 7.1.1 in the 2010 New England Tree Fruit Management Guide - Unfortunately, there are a number of errors in Table 7.1.1 on Pages 71-72 in the new 2010 New England Tree Fruit Guide. This is the table called “Activity Spectrum of pome fruit insecticides and acaricides” which gives the pesticide efficacy ratings for key orchard pests. Something evidently happened in the revision/editing process. Until we get this corrected, please consult the 2009 version of the New England Tree Fruit Management Guide or you can consult the Cornell version which is online at
http://ipmguidelines.org/TreeFruits/content/CH07/default-1.asp
New England Tree Fruit Management Guide
The 2010 New England Tree Fruit Management Guide is now available. The Guide includes extremely useful information, particularly with regard to pesticides & pest management. The Guide covers all tree fruit crops grown in New England including apples, pears and stone fruit. They are now available from the UConn Communications and Information Technology Office; Unit 4035; 1376 Storrs Rd.; Storrs, CT 06269 or (860)486-3336. The cost of $35 includes Shipping & Handling. Credit cards are accepted.
New England Small Fruit Pest Management Guide is hot off the press!
The 2010-2011 New England Small Fruit Pest Management Guide was just revised and is also available from the UConn Communications and Information Technology Office; Unit 4035; 1376 Storrs Rd.; Storrs, CT 06269 or (860)486-3336. The cost of $16 includes Shipping & Handling. Credit cards are accepted.
Lorraine
Lorraine Los
Fruit Crops IPM
Coordinator
Plant Science Department, U-4067
University of Connecticut
Storrs,
CT 06269-4067
(860)486-6449
(Phone)
(860)486-0682 (Fax)
Lorraine.Los@uconn.edu
| 2010 Fruit Pest Messages |
| April 29, 2010 |
New England Tree Fruit Management Guide
The 2010 New England Tree Fruit Management Guide is now available. The Guide includes extremely useful information, particularly with regard to pesticides & pest management. The Guide covers all tree fruit crops grown in New England including apples, pears and stone fruit. They are now available from the UConn Communications and Information Technology Office; Unit 4035; 1376 Storrs Rd.; Storrs, CT 06269 or (860)486-3336. The cost of $35 includes Shipping & Handling. Credit cards are accepted.
New England Small Fruit Pest Management Guide is hot off the press!
The 2010-2011 New England Small Fruit Pest Management Guide was just revised and is also available from the UConn Communications and Information Technology Office; Unit 4035; 1376 Storrs Rd.; Storrs, CT 06269 or (860)486-3336. The cost of $16 includes Shipping & Handling. Credit cards are accepted.
UConn IPM Tree Fruit articles
UConn IPM Small Fruit articles
This information was developed for conditions in the Northeast. Use in other geographical areas may be inappropriate.
The information in this material is for educational purposes. The recommendations contained are based on the best available knowledge at the time of printing. Any reference to commercial products, trade or brand names is for information only, and no endorsement or approval is intended. The Cooperative Extension system does not guarantee or warrant the standard of any product referenced or imply approval of the product to the exclusion of others which also may be available.All agrochemicals/pesticides listed are registered for suggested uses in accordance with federal and Connecticut state laws and regulations as of the date of printing. If the information does not agree with current labeling, follow the label instructions. The label is the law.Warning! Agrochemicals/pesticides are dangerous. Read and follow all instructions and safety precautions on labels. Carefully handle and store agrochemicals/pesticides in originally labeled containers immediately in a safe manner and place. Contact the Connecticut Department of Environmental Protection for current regulations.The user of this information assumes all risks for personal injury or property damage.Issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture. Kirklyn M. Kerr, Director, Cooperative Extension System, The University of Connecticut, Storrs. The Connecticut Cooperative Extension System offers its programs to persons regardless of race, color, national origin, sex, age or disability and is an equal opportunity employer.