NC Strawberry Advisory (Vol.2 No.5)


Berry-mg electronic newsletter
March 9, 2000 - Strawberry Advisory

Well, its going to be a hot one today, going into low 80's this Thursday March 9, 2000, and again tomorrow we'll be seeing almost late spring-like temperatures. A cooler spell is ahead, starting Saturday-Sunday, and night temperatures will be back down into the mid 30's early next week!

FYI: I have re-activated the Extension Strawberry Teletip this morning and these will be recorded each week through the rest of the season.

All you have to do to get the Extension Strawberry Teletip is:
a) call 1-800-662-7301
b) press "1" on the touchtone phone
c) press "5146" when requested for 4-digit advisory number

NOTE: The length of these teletips is very very short! My message got cutoff at the point where I started speaking about the second weekly fungicide spray - so, please see section 4 below for more information about the second cover spray and beyond... These teletips can only provide highlights, so please encourage your growers to utilize the berry-mg electronic newsletter for more in-depth advisories.

You can read these same advisories by:
Sending a message to almanac@ces.ncsu.edu
Then, just send the one line message: subscribe berry-mg

Also, in the event of possible frost freeze: ask for
Extension Teletip "5147" - these advisories on 5147 will be updated on a daily basis in frost/freeze period.

Strawberry Frost/freeze advisory: (none being played presently)

a) call 1-800-662-7301
b) press "1" on the touchtone phone
c) press "5147" when requested for 4-digit advisory number

BUSY BUSY DAYS!
1. Weather - Crop Status
It doesn't get any busier for a strawberry grower than right now - so let's not waste a moment and get right down to how the 2000 crop is shaping up and some of the things we need to be thinking about in the second week of March. One year ago was quite a contrast to last year! Last year we had over 14 nights of frost freeze control, and by this date in March we had run our system at Clayton Central Crops six times. In fact, on March 8, 1999, at 6 am we recorded a low temperature of 23 F.

But looking at weather report and extended forecasts, I do not see imminent threat of frost/freeze. Several "old-timers" have informed me though that we are due for "something". Just in case they are right, I hope you got your digital thermometer, and checked out overhead irrigation system pretty carefully, just in case temperatures do suddenly start dropping down to 32 or below anytime soon.

At this stage, we are out from under the threat of the "arctic blasts" that swept in here last year. And, as we get closer to middle of March, I start feeling a little more relaxed about those kinds of problems.

8-10 day outlook:
<---------- 1-7 DAY FORECAST ------------> <8-10 DAY OUTLOOK>
DATE Mar 8 9 10 11 12 13 14 15 16 17
DAY WED THU FRI SAT SUN MON TUE WED THU FRI
------------------------------------------------------------------------------
MAX AIR TEMP (F) 83 83 83 70 58 60 61 65 63 62
MIN AIR TEMP (F) 55 56 53 52 42 36 36 38 38 39
PRECIP PROB (%) 1 6 11 85 53 24 22 31 33 35
AVG DAILY RH (%) 55 57 58 94 81 62 62 61 63 64
AVG WND SPD (mph) 7 8 10 10 10 8 8 8 8 8

You can obtain other sites in NC from www.smallfruits.org

2. Problems identified on recent site visits:
a) Immediate need to pull "kept crowns" that are caught beneath the plastic, out into the open sunlight.
b) Immediate need to initiate drip fertigation program.
c) Immediate need to send in petioles for petiole nitrate testing and leaf blades for full tissue analysis

3. Insects and Mites: The most severe outbreaks start in late winter (now). Spider mites are present in large numbers before causal symptoms can be recognized without close examination of the undersides of leaves, pulled at random. Temperatures above 65 degrees will intensify activity. With steady increase to above 70 degrees at the growing point mites from egg to egg in less than 14 days. Weekly examinations to lower leaves and into buds will reveal mites and aphids. Also look for mite eggs.

Lorsban - eastern growers are out of that period now for this chemical's use (it is only for pre-bloom) for strawberry weevil control.

4. Disease report: Some evidence of Angular Leafspot (bacterial disease) seen yesterday. Copper materials, like Kocide, can be used, but you run risk of phytoxicity. Virtually no control, other than disease free plants. This disease is one that frequently does come in on Canadian plant material.

By this time all operations should have completed leaf and runner removal. For your botrytis or gray mold control program, Dr. Frank Louws, Extension Plant Pathologist, notes that the first cover spray should be initiated during early bloom (10%) using Captan + Topsin-M or Captan + Benlate. For the second and possibly third application at weekly intervals, use Elevate. During a "full-bloom" situation (possibly the third or fourth application), apply the Captan + Topsin-M or Captan + Benlate tank mix. For subsequent applications, alternate Captan 2x and Elevate 2x. Modifications of this approach would be to reduce the frequency of applications during warm-dry weather and tighten up the frequency during cooler-wet periods and according to the key principles outlined above.

Quadris is still under emergency registration until April 12, 2000 - for anthracnose control.

5. Mulches - some growers will add a nice straw mulch between the plastic beds for the ultimate picking experience, and this can be done relatively soon.

6. Ryegrass control - Poast should have already gone out for control of ryegrass in the aisles. There are no products registered currently for vetch control - hand removal right now is best.

7. Market opportunities: I know folks are getting really excited about having some fresh strawberries from your farm! Now is the time to:
a) Check inventory of picking containers
b) Get scales checked with NCDA
c) Get signs ready to put out on roadsides.

Wishing you a great weekend and week ahead!

Barclay Poling
Extension Specialist (Strawberries and Muscadines)