Pea moth monitoring and forecasting has ended for 2019, although you can contact Becky Howard on 01780 781351 for further advice.
A spray date can be obtained below during the forecasting period, based on a computer prediction, 3 - 4 days after reaching a threshold in traps.
Traps should be placed in pea crops in mid-May and monitored three times each week. In combining peas, when 10 or more moths are caught in either trap on two consecutive occasions, monitoring of temperature should commence to predict your spray date. In vining peas a lower threshold of damage is tolerated and traps should be used as an indication of moth presence. Threshold dates may vary for different regions and it is important to monitor populations in your region to accurately predict spray date. Timing of sprays is related to egg development and this is affected by temperature. Control of the larvae must be carried out following egg-hatch and before they reach the pod, and the monitoring system will accurately predict this.
On the predicted spray date, crops which are at the first pod set stage or which have flowered should be sprayed, but later crops should only be sprayed when they reach first pod set. Crops with green pods are susceptible to damage. A second application should be applied 10-14 days later.