Conditions: Warm, sunny and dry conditions over the last 2 weeks were ideal for field work. Timely rains May 10-12 brought 20 mm (5 to 50 mm) of welcome precipitation across eastern Ontario. With most of the cereals, new forage seedings, corn and part of the soybean acreage seeded/planted between April 27th and May 10th, the fertilizer/seed supply/delivery chain was stretch to the maximum. Next stress point will be the weed control, which will literally need to occur simultaneously for all crops.
Forages: After suffering through varying degrees of alfalfa winter kill over the last few years, growers are currently seeing one of their best overwintering alfalfa crop. Alfalfa fields not harvested last fall have 8 to 13 inches of growth, while fields harvested last fall typically have 4 to7 inches of growth. Even fields harvested mid-September during the Critical Fall Harvest Period overwintered well, although spring growth is roughly half of the growth in found in fields not harvested last fall. Alfalfa growth/development is a few days ahead of normal, pointing to a late May harvest, while grass growth is a few days behind long term average.
New alfalfa seedings are mostly at the unifoliate stage. It is best to target the early part of the weed control window for herbicide application, as small weeds are easier to control than large ones and alfalfa at the 1st to 2nd trifoliate stage is less sensitive to 2,4-DB than alfalfa at the 3rd to 4th trifoliate stage (Figure 1).
Figure 1. Alfalfa Growth Stages
Alfalfa Growth Stages
Excellent alfalfa winter survival and high stored forage inventories provides a great opportunity to rotate weaker forage stands to other crops and take advantage of the nitrogen credit from alfalfa and the 10 – 15% rotational yield benefit in the subsequent crop.
Alfalfa snout beetles (ASB) have emerged. The larval stage of the pest is quite destructive, gouging deep galleries in the roots and even severing roots completely at times. To date, ASB has been identified in parts of Grenville and Leeds counties. Sightings outside of Leeds and Grenville should be reported. The beetles (Figure 2.) resemble alfalfa weevils, but are gray in colour and 2 to 3 times larger.
Figure 2. Alfalfa snout beetle
Alfalfa Snout Beetle
Cereals: Winter wheat is at growth stage 31 – 32 on the Zadok’s Scale (Figure 3). The crop will soon be beyond the herbicide application window.
Figure 3. Cereal Growth Stages
Cereal Growth Stages
Spring cereals planted at the end of April are at growth stage 10 (Zadok’s Scale) and will soon start to tiller. If applying herbicide at the end of the herbicide spray window, the addition of a fungicide with the herbicide has shown a yield increase of about 1.5 bushel per acre in spring wheat.
Cereal growers with varieties prone to lodging and/or using high nitrogen rates should consider applying a growth regulator. See product label for application window.
Corn: Across eastern Ontario, over 90% of corn is planted and emergence is good. For acreage yet to be planted, adapted hybrids can be planted until May 20th.
There are several methods of staging early corn growth for herbicide application (see Figure 4). The Guide to Weed Control (Pub 75) uses the leaf over method, which counts leaves that have emerged from the whorl and are starting to arch over. Most herbicide labels refer to this method of leaf counting, but check the label or contact the product representative to confirm.
Figure 4. Corn Growth Stages
Corn Leaf Stages
Soybeans: Close to 50% of the intended soybean acreage is planted.
Crop Insurance Update: Online acreage reporting now available. Ontario grain and oilseed producers with Production Insurance can report their acreage on Agricorp.com from May 13 until the June 30 reporting deadline.
With online reporting, producers can:
Report their acres any time, 24 hours a day, 7 days a week
Report more than one crop at a time
Get an immediate confirmation number for their acreage report.
Producers with new account information or landlord/sharecrop arrangements must contact Agricorp to report.
Weed ID: The weed brought in by Bryan Cook was identified as celery-leaved buttercup, (Ranunculus sceleratus L.) by Stephen Darbyshire, AAFC, Ottawa. It is an annual or short-lived perennial, reproducing only by seed. Celery-leaved buttercup (Figure 5) is found in southern and western Ontario in swamps, ditches, roadsides, pastures, fields, mudflats and the edges of ponds and lakes.
Figure 5. Celery-leaved buttercup
Celery-leaved buttercup
Resources
CropLine – 1-888-449-0937
Eastern Ontario Crop Diagnostic Day will be on Tuesday, July 21, 2015 at the Winchester Research Station, University of Guelph. Still opportunity to have input into the demonstration stops.
Source: Fieldcropnews