All entries for March 2014

Pollen beetles on the move

The recent warm weather has brought adult pollen beetles out of hibernation. Dandelion flowers are one of their favourite locations:

Rosemary Collier : 30 Mar 2014 11:41 |  Comments (1) |  Close comments |  Report a problem

First cabbage root flies captured

We put out yellow water traps and sticky traps (for carrot fly) on 11th March and have been catching a few bean seed flies in the water traps since then. We had caught 2 male and 1 female cabbage root fly in the water traps (3 traps) when they were emptied on 25th March. Cabbage root fly and carrot fly activity is predicted to be relatively early (particularly when compared with 2013) but there is still some time to go before egg-laying starts. Once they have emerged, female cabbage root flies require a bit of time to feed, mate and mature their eggs. This is equivalent to about 80 day-degrees above 6°C. No carrot flies have been captured yet.

Further details can be found in the HDC Pest Bulletin.

Rosemary Collier : 28 Mar 2014 17:20 |  Comments (0) |  Close comments |  Report a problem

Updated day–degrees – 2014 now ahead!

Updated day-degree accumulations for Wellesbourne show that 2014 is currently the warmest of the last 5 spings day-degrees_19_march.pdf.

Rosemary Collier : 23 Mar 2014 18:50 |  Comments (0) |  Close comments |  Report a problem

Start of the 2014 pest season

The weather has been very mild this winter and people have started to ask how early certain pests will appear this spring, bearing in mind that the rate of insect development is largely dependent on temperature. Rothamsted Research recently released their forecasts for 2014 for peach-potato aphid, potato aphid and cabbage aphid: aphid_news_forecasts_2014.pdf. The general message is that, if spring does not throw any wildly abnormal conditions at us, aphids will be flying con-siderably earlier than normal.

Just to put 2014 in perspective, we have calculated accumulated day-degrees above 4.4^oC (the base temperature we use for several species of aphid) from 1 January for 2014 and the four previous years: wellesbourne_day-degrees.pdf. At present, 2014 is only slightly ahead of 2012.

Rosemary Collier : 16 Mar 2014 20:24 |  Comments (0) |  Close comments |  Report a problem