Root, bulb, leafy and brassica vegetable pest report – 6 June 2013

See below for the degree days accumulated from April 1st until June 6th, 2013.These values are provided as guidelines only. Local environments, soil type, field history, etc. are likely to influence activity of these pests.

Thresholds for emergence of first generation onion maggot fly adults have been reached in all areas. On sticky traps used for monitoring by the Muck Crops Research Station, onion maggot fly counts have been increasing since last week. First generation cabbage maggot adults have likely emerged in all areas for which degree days are calculated for. For all areas, accumulated degree days indicate emergence of first generation carrot rust fly adults, if resident populations are present. Carrot rust flies were caught earlier this week on traps at the Muck Crops Research Station in the Holland Marsh. If resident populations are present, carrot weevil have likely started to lay eggs in all areas as indicated by accumulated degree days. In the Windsor area, degree days indicate 90% oviposition of carrot weevil. Tarnished plant bugs have likely emerged in all areas; however, the Muck Crops Research Station scouts have not seen tarnished plant bugs on celery in the Holland Marsh yet. I’ve seen tarnished plant bug on sticky traps as by-catch though. Overwintering leafhopper eggs have likely started to hatch in all areas. Local leafhopper adults will likely start emerging in the Windsor area in about 7-10 days. No leafhoppers have been reported in the Holland Marsh.

Onion thrips have been seen on transplanted onions. Be sure to scout for thrips.

Area

Onion Maggot (base 4)

Cabbage Maggot (base 6)

Carrot Rust Fly (base 3)

Carrot Weevil (base 7)

As of

Bradford/Holland Marsh*

488.7

n/a

545.1

337.6

06/06/2013
London

496.5

391.2

552.8

345

06/06/2013
Wellington

428.3

331.2

482.2

287.5

06/06/2013
Windsor

602.0

488.6

662.6

435.9

06/06/2013
Thedford

508.3

404.8

565.4

360.8

06/06/2013
Delhi

466.7

365.9

522.2

320.1

06/06/2013
Ridgetown

498.2

395.4

554.9

347

06/06/2013

 

Area

Tarnished Plant Bug (base 12)

Leafhopper (base 9)

GDD (base 5)

As of

Bradford/Holland Marsh*

149.6

253.7

436.1

06/06/2013
London

152.9

260.3

442.3

06/06/2013
Wellington

111.6

207.5

377.4

06/06/2013
Windsor

215.9

339.3

544

06/06/2013
Thedford

170.6

277.4

454

06/06/2013
Delhi

131.8

235

414.4

06/06/2013
Ridgetown

160

263.9

445.2

06/06/2013

Data provided by Environment Canada.

*Data provided by Muck Crops Research Station, University of Guelph.

Degree day model information for pests 

Thresholds

1st Generation

2nd Generation

3rd Generation

Onion Maggot

210

1025

1772

Cabbage Maggot

314-398

847-960

1446-1604

Carrot Rust Fly

329 – 395

1399-1711

n/a

Carrot Weevil

138-156 (first egg-laying)
455 (90% of eggs laid)

No model available

n/a

Tarnished Plant Bug

40

n/a

n/a

Aster Leafhopper

128 (overwintering egg hatch)

390 (local adult emergence)

n/a

n/a

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s