Week 24 (June 8th to June 13th) 2020

Compiled by: Dr M.Gaffney (michael.gaffney@teagasc.ie)

Field Vegetable Pests

This weekend there was an influx of Diamond Back Moth (Plutella xylostella) into our monitoring site at Kinsealy, North Dublin. While it is difficult to ascertain exact numbers, moth activity in the crop was obvious. Given the ability of this pest to rapidly defoliate crops, it would be advisable for growers of susceptible crops (mostly Brassicas) to monitor the situation in their fields. 

 

There was no obvious Diamond Back Moth activity at our monitoring plots in Ashtown, Dublin so it is difficult to ascertain how widespread its dispersal may be. The moth itself is relatively small, with a gray/brown colouration, with the characteristic cream band that forms a diamond shape along its back. They are easily disturbed as you walk through the crop, so it is relatively easy to spot them. No Silver Y moths were identified in the crop.

Carrot Root Fly activity has decreased over the last number of weeks, with peak numbers being recovered in week 20, with an average of 18 flies per trap. This week, the mean no. of flies per trap across both sites was 3.6. However it seems likely we are now past the peak of first generation activity in North Dublin.

Cabbage Root Fly activity has decreased in recent weeks, with no eggs being recovered from any of the 6 plants tested across our 2 Dublin sites this week. Below is a graph of cabbage root fly egg numbers this season so far. It seems likely that the peak of first generation egg laying has finished. We would expect second generation egg laying to commence in the next 2 to 3 weeks.

Aphid activity has been very high for the last 2 weeks, and untreated crops are now heavily infested. While there is a good level of parasitoid and predator activity with the crops, some plants are being challenged. Levels of Cabbage Mealy Aphid (Brevicoryne brassicae) seem particulary high on our untreated crops in Kinsealy (picture below), while Flea beetle damage remains very evident on brassica crops in Ashtown. There are also high levels of aphid in untreated carrot crops, particularly the Willow Carrot Aphid, (Cavariella aegopodii), with some characteristic reddening of the foliage occurring.

Broccoli plant with a large Cabbage Mealy Aphid population

Fruit Pests

Spotted wing Drosophila trap counts from our Kinsealy and Ashtown locations have decreased significantly in the last 2 months, as is normally observed, with an average catch of 1 adult SWD across 8 traps at 2 sites. However fruit baited traps have recovered a number of eggs, so egg laying females are active and our ‘in crop’ Strawberry and Raspberry traps have found female SWD present this week. If not already, growers should commence monitoring immediately and consult their advisor if SWD is found to be present in crops. The number of Light Brown Apple Moth recovered this week using a pheromone trap in a hedgerow at our Kinsealy monitoring site were 23, which as you can see from below is relatively consistent since activity was first noticed in week 17.

The information included in this update are observations from experimental plots in the Dublin area and should not be taken as advice. Growers concerned should monitor their own production areas and engage with a qualified advisor is necessary.

Further Information and Samples to: Dr Michael Gaffney, Teagasc Ashtown, Ashtown, Dublin 15

T: 0871205840 E: Michael.Gaffney@Teagasc.ie Twitter: @Mick_Gaffney

 

Week 19(May 4th to May 11th) – 2020

Field Vegetable Pests

The recent low day and night temperatures seem to have influenced general insect behaviour as the number of insects discovered in water and aerial traps is noticeably reduced this week.

There is evidence of Cabbage Root Fly activity at both monitoring sites, however the number of adults stuck on yellow sticky traps and in water traps was lower this week, but that was a general trend for most insects we would usually observe. Egg laying occurred at both sites, with an average of 1.3 eggs per plant being found at Kinsealy (2.3 per plant last week), and 7.3 eggs per plant at Ashtown (11 per plant last week). In previous years (2018 apart) peak egg occurred in and around second week of May.

Carrot root flies have been recorded on yellow sticky traps at both North Dublin locations with 6 adults per trap at Kinsealy (5.3 last week) and 18 adults per trap recovered at Ashtown (An increase from 11 last week). As carrot root flies have been active for a number weeks now, growers with susceptible crops should monitor the situation in their crops.

The number of migrating Aphids caught both in water traps at both sites and in the 6m suction trap at Ashtown was lower this week than last, however the difference in environmental conditions is likely a factor. There was a greater diversity in the number of species found. Some winged Cabbage Mealy Aphid was observed at low levels in our monitor plots of Brassicas. An academic study from 2010 indicated, that even if plants are water stressed (for 2 weeks), this did not alter Cabbage Mealy Aphid feeding behaviour or rate, so growers should be proactive in monitoring crops for signs of Aphid activity.

There is no evidence of migratory moths such as Diamond Back Moth or Silver Y moth being active in crops at either site. In 2018 the first arrivals of DBM in the Dublin area occurred around week 18. As observed last week, Flea beetle damage is continuing to be obvious and widespread at our Ashtown plot.

Fruit Pests

Spotted wing Drosophila activity at our Kinsealy and Ashtown locations has been obvious over the winter period. This week the average trap catch at Kinsealy was 11.7, down from 46 last week and a decrease from 204.3 per trap two weeks ago and 3 adults per trap at Ashtown (down from 8.3 last week and 23.6 the week before week). Our ‘in crop’ Strawberry and Raspberry traps had no SWD present this week. Growers should commence monitoring immediately and consult their advisor if SWD is found to be present in crops.

The number of Light Brown Apple Moth recovered this week using a pheromone trap in a hedgerow at our Kinsealy monitoring site increased again this week, with an average of 13 per trap recovered, up from an average of 8 the previous week. Light Brown Apple moth has a wide host range and can attack a range of vegetable, ornamental and fruit crops.

The information included in this update are observations from experimental plots in the Dublin area and should not be taken as advice. Growers concerned should monitor their own production areas and engage with a qualified advisor is necessary.

Further Information and Samples to: Dr Michael Gaffney, Teagasc Ashtown, Ashtown, Dublin 15

T: 0871205840 E: Michael.Gaffney@Teagasc.ie Twitter: @Mick_Gaffney

                                                                                                                                          

                            

                                                                                                                                   

 

Week 18 (April 28th to May 4th) 2020

Field Vegetable Pests

Cabbage Root Fly remain active in both monitoring sites, with plenty of adults stuck on yellow sticky traps and in water traps. Egg laying is now evident at both sites, with an average of 2.3 eggs per plant being found at Kinsealy, and 11 eggs per plant at Ashtown. In previous years (2018 apart) peak egg laying occurred in the second week of May.

Carrot root flies have been recorded on yellow sticky traps at both North Dublin locations, which is not unusual, with 5.3 adults per trap at Kinsealy and 11 adults per trap recovered at Ashtown (An increase from 0.4 and 4 last week). As carrot root flies have been active for a number weeks now, growers with susceptible crops should assess the situation in their crops.

The number of migrating Aphids caught both in water traps at both sites and in the 6m suction trap at Ashtown has increased this week, with a small number of Carrot Willow aphid and Cabbage Mealy Aphid being present. Given the mild weather to date, growers should assess fields for the presence of aphids on susceptible crops. The AHDB in the UK have predicted that the combination of a mild winter and good weather might mean some agriculturally important aphid species may fly earlier this year than previous years.  

There is no evidence of migratory moths such as Diamond Back Moth or Silver Y moth being active in crops at either site. In 2018 the first arrivals of DBM in the Dublin area occurred around week 18. Flea beetles and the damage they cause to leaves are noticeable in Brassica crops in the observation plots (Picture Below).

Fruit Pests

Spotted wing Drosophila activity at our Kinsealy and Ashtown locations has been obvious over the winter period. This week the average trap catch at Kinsealy was 46, a decrease from 204.3 per trap last week and 8.3 at Ashtown (down from 23.6 last week). Our monitoring project would have observed a decrease in hedgerow catches into May and June in previous years, with increases again from July onwards. Understanding the reason for this is part of an ongoing project. Our ‘in crop’ Strawberry and Raspberry traps had no SWD present this week. Growers should commence monitoring immediately and consult their advisor if SWD is found to be present in crops.

 The number of Light Brown Apple Moth recovered this week using a pheromone trap in a hedgerow at our Kinsealy monitoring site increased again this week, with an average of 8 per trap recovered. Light Brown Apple moth has a wide host range and can attack a range of vegetable, ornamental and fruit crops.

Further Information and Samples to: Dr Michael Gaffney, Teagasc Ashtown, Ashtown, Dublin 15

T: 0871205840 E: Michael.Gaffney@Teagasc.ie Twitter: @Mick_Gaffney

Pest Update Week 17 – April 20th to 27th 2020

Pest Update Week 17 2020

Field Vegetable Pests

Cabbage Root Fly remain active in both monitoring sites, with plenty of adults stuck on yellow sticky traps and in water traps. Egg laying is now evident at both sites, with an average of 8.3 eggs per plant being found at Kinsealy, and 5.3 eggs per plant at Ashtown (an increase on 0 and 2.3 eggs per plant recovered last week). In previous years (2018 apart) peak egg laying occurred in the second week of May.

Carrot root flies have been recorded on yellow sticky traps at both North Dublin locations, which is not unusual, with 0.4 adults per trap at Kinsealy and 4 adults per trap recovered at Ashtown. In previous years trap counts have been much higher, so the expectation is that numbers will increase in the next week. Females require time to mate and mature before they commence egg laying.

The number of migrating Aphids caught both in water traps at both sites and in the 6m suction trap at Ashtown has increased this week, however none of our target species (Cabbage Mealy aphid, Carrot-Willow Aphid or Peach-Potato Aphid) were identified. However it should be noted that the AHDB in the UK have predicted that the combination of a mild winter and good weather might mean some agriculturally important aphid species may fly earlier this year than previous years.  

There is no evidence of migratory moths such as Diamond Back Moth or Silver Y moth being active in crops at either site. In 2018 the first arrivals of DBM in the Dublin area occurred around week 18. The diversity of insect species recovered from the 6m aerial suction tower increased this week, with a number of Flea beetles and grain weevils recovered. Also a number of common green capsids were also observed in the trap. The water traps located in crops showed the a number of different species of parasitic wasps were now becoming active.

Fruit Pests

Spotted wing Drosophila activity at our Kinsealy and Ashtown locations has been obvious over the winter period. This week there was a noticeable increase in the average trap catch of 204.3 per trap in Kinsealy and 23.6 at Ashtown. Our ‘in crop’ Strawberry and Raspberry traps had no SWD present this week. Growers should commence monitoring immediately and consult their advisor if SWD is found to be present in crops.

The number of Light Brown Apple Moth recovered this week using a pheromone trap in a hedgerow at our Kinsealy monitoring site increased. Light Brown Apple moth has a wide host range and can attack a range of vegetable, ornamental and fruit crops.

Further Information and Samples to: Dr Michael Gaffney, Teagasc Ashtown, Ashtown, Dublin 15

T: 0871205840 E: Michael.Gaffney@Teagasc.ie Twitter: @Mick_Gaffney

 

 

Pest Update Week 16 2020 – April 13th to 19th

Pest Update 2020 – April 13th to 19th                                            

 

Compiled by: Dr Michael Gaffney                                                                                                                                              

Field Vegetable Pests

Cabbage Root Fly activity is noticeable in the plots, with plenty of adults stuck on yellow sticky traps and in water traps, however no eggs have been found at our Kinsealy site this week. In Ashtown, an average of 2.7 eggs were recovered from Broccoli plants, indicating that some egg laying has commenced. In 2017 egg laying commenced in week 16 also, with peak egg laying occurring in the second week of May.

Carrot root flies have were recorded on yellow sticky traps at both North Dublin locations, which is not unusual. Females require time to mate and mature before egg laying, but a spell of good weather can increase the speed of this development.

Carrot root fly can be quickly identified on yellow sticky traps. They have a tendency to hit the trap side on, so usually present a side profile. The legs are red and usually trailing backwards. The head has a reddish colour and can appear slightly separated from the fly ‘body’. 

The number of migrating Aphids caught both in water traps at both sites and in the 6m suction trap at Ashtown were very low, and no species of agronomic importance were identified. However it should be noted that the AHDB in the UK have predicted that the combination of a mild winter and good weather might mean some agriculturally important aphid species may fly earlier this year than previous years.  

Again, while there are some reports of silver Y moths or diamond back moths being found in traps in the UK, none have been observed in traps or within monitor crops. In 2018 the first arrivals of DBM in the Dublin area occurred around week 18.

A single Flea beetles and a single grain weevils were recovered from the 6m suction trap this week.

Fruit Pests

Spotted wing Drosophila activity at our Kinsealy and Ashtown locations has been obvious over the winter period. This week there was an average trap catch of 107 per Trap in Kinsealy and 15 at Ashtown. This is comparable to the numbers caught in previous years. Our in crop Strawberry traps had no SWD present and a single female was found in traps located in our Raspberry crop. Growers should commence monitoring immediately and consult their advisor if SWD is found to be present in crops.

A single Light Brown Apple Moth was recovered from a pheromone trap in North Dublin.

Further Information and Samples to: Dr Michael Gaffney, Teagasc Ashtown, Ashtown, Dublin 15

T: 0871205840 E: Michael.Gaffney@Teagasc.ie Twitter: @Mick_Gaffney

Pest Update Weeks 18&19 (Apr 19th – May 11th)

Field Vegetable Pests

Diamond Back Moths have now arrived at our monitoring plots in Ashtown and Kinsealy in North Dublin. This migration seems to be coming from Scandinavia, through the UK (reports of sightings in Lincolnshire late last week). While the numbers observed seem low, the continued good weather this week may see an increase in population. It would be advisable for all brassica growers to check crops and take appropriate control measures. Monitoring these moths is relatively easy, as they move quickly up off the foliage when disturbed by people walking through the crop. They can be identified by the white markings on their back (picture below), thought to be diamond in shape.

Cabbage root fly activity increased greatly in week 17 with an average of 77 adults caught on sticky traps, however egg laying remains relatively as predicted with 9 egg per plant recovered in Week 17 and 5.8 eggs per plant in week 18. The rainfall over these 2 weeks may have slowed egg laying, but the relatively good weather of the last 5 days may see an increase in this week’s counts (results will be available tomorrow). At our new monitoring plot in Ashtown, egg laying decreased in Week 18 to 5.8 egg/plant, from 16.3 eggs/plant in Week 17.  In 2018 the Week 19 was the peak of Cabbage Root Fly egg laying (12 egg/plant) at the Kinsealy site.

Carrot Root Fly activity is extremely high at Kinsealy where our over wintered carrot plot was located with an average of 193 adults flies caught per trap in week 17 and 112 adults caught per trap in week 18. Growers should be actively monitoring traps in fields with emerged carrots and taking appropriate control measures if required. At our newly drilled carrot plot in Ashtown an average of 4 carrot root fly adults per trap were recovered in week 18 (week 17 average 5 carrot root flies per trap).

Aphid activity is increasing, with an increase in the number of winged Aphids appearing in water traps. Both Carrot-Willow Aphids (Cavariella aegopodii) and Cabbage Aphids (Brevicoryne brassicae) have been recovered from water traps in brassica crops in Dublin this week. Aphid activity is also noticeable on newly emerged carrots and module brassicas. Again growers need to monitor aphid levels in crops.

Brassica weevils and Flea beetles are now obvious on crops and some flea beetle damage has been observed.

Beneficial Insects

Beneficial predators and parasitoids remain very abundant in crops. Growers should apply best IPM practices to preserve and maintain these populations.

Spotted Wing Drosophila activity is obvious in the 3 traps at our Kinsealy location.  The numbers recovered are higher than were observed last year (average 151 per trap) and as fruit is now growers should be actively monitoring and taking a whole farm IPM approach to managing this pest.

Tortrix moth activity is again becoming noticeable in crops, particulary covered crops. Growers should be vigilant for activity in crops and check plant leaves regularly for caterpillar activity.  

 

Further Information and Samples to: Dr Michael Gaffney, Teagasc Ashtown, Ashtown, Dublin 15

T: 0871205840 E: Michael.Gaffney@Teagasc.ie Twitter: @Mick_Gaffney

 

 

 

 

Pest Update – Week 17

Latest Update: Week 17 (April 22^nd to 29th)

Compiled by: Dr Michael Gaffney                                                                                                                                              

Field Vegetable Pests

Cabbage root fly egg laying has continued with 9 eggs per plant being found this week. This is continuing the trend for increasing weekly counts, as observed to date: week 13 (1.5 eggs / plant), week 14 (2.8 eggs / plant), week 15 (1.8 eggs / plant) and week 16 (8 eggs / plant). However there was sizable jump in the number of adult cabbage root fly being observed on sticky traps, from 21 in week 16 to 115 this week, indicating that peak activity is approaching. This week we also observed egg laying at our monitoring site in Ashtown for the first time this year (8.5 eggs per plant). With the weather forecast to improve, it’s likely we will see an increase in egg laying over the next few weeks. This corresponds to 2016 and 2017, peak first generation egg laying occurred in Dublin and Kilkenny in the second and third week of May (2018 data affected by snow cover). 

Carrot root flies have also been active since early March, in an untreated overwintered carrot plot in North Dublin. The number of flies recovered on traps jumped this week to an average of 62.5, an increase on the number recovered in the previous 4 weeks (0.25, 6.25, 3.5 and 17).  

The number of migrating Aphid pests caught in water traps in monitor plots continues to be low but the overall catches are increasing. No brassica aphids have been recovered from water traps within crops. Similar to previous weeks very low numbers of Willow-Carrot aphid were recovered from water traps. It should also be noted that aphid activity on our untreated over wintered carrot crop is obvious.  No silver Y moths or diamond back moths have been observed in traps or within monitor crops.

Some brassica weevils were observed in the water traps this week for the first time.

Fruit Pests

Spotted wing Drosophila activity at our Kinsealy and Ashtown locations has been obvious over the winter period. In week 15 we observed an average of 198 SWD per trap at Kinsealy and 22 individuals per trap at our Ashtown site and in week 16 we observed an average of 130 SWD per trap at Kinsealy. These early season numbers are higher than we have previously observed and potentially pose a threat to crops. Growers should commence monitoring immediately and consult their advisor if SWD is found to be present in crops.

Further Information and Samples to: Dr Michael Gaffney, Teagasc Ashtown, Ashtown, Dublin 15

T: 0871205840 E: Michael.Gaffney@Teagasc.ie Twitter: @Mick_Gaffney

Pest Update – Week 15 (2019)

                                                                                                                      

Field Vegetable Pests

Cabbage Root Fly egg laying has continued, with 1.8 eggs per plant being found this week. This is similar to week 13 (1.5 eggs / plant) and week 14 (2.8 eggs / plant). It’s possible the colder weather is affecting the maturation of female flies as a significant number of adult flies are being caught in the crop (27 flies per sticky trap), but there has not been a corresponding increase in egg laying. An increase in temperature could see a significant increase in the number of eggs being found. In 2018, we commenced monitoring in week 15 where 3.6 eggs per plant were recovered and this increased in week 16 to 34.3 eggs. In 2017, egg laying was not detected until week 16. In 2016 and 2017, peak first generation egg laying occurred in Dublin and Kilkenny in the second and third week of May (2018 data affected by snow cover).

Carrot Root Flies have also been active since early March, in an untreated overwintered carrot plot in North Dublin. The number of flies recovered on traps increased this week to an average of 17, an increase on the number recovered in the previous 3 weeks (0.25, 6.25 and 3.5). New observation plots were drilled in North Dublin (but are yet to emerge) and will be used to monitor for adult activity and egg laying. Females require time to mate and mature before egg laying, but a spell of good weather can increase the speed of this development.

The number of migrating Aphid pests caught in water traps in monitor plots continue to be relatively low. No Brassica Aphids have been recovered from water traps within crops. Similar to weeks 13 and 14 very low number of Willow�Carrot aphid were recovered from water traps. It should also be noted that aphid activity on our untreated over wintered carrot crop is obvious. No Silver Y Moths or diamond back moths have been observed in traps or within monitor crops.

 No Flea Beetles or Weevils were recovered in week 15.

Fruit Pests

Spotted Wing Drosophila (SWD) activity at our Kinsealy and Ashtown locations has been obvious over the winter period. In week 15 we observed an average of 198 SWD per trap at Kinsealy and 22 individuals per trap at our Ashtown site (both these counts refer to a 2 week trapping period). Growers should commence monitoring immediately and consult their advisor if SWD is found to be present in crops.

This report was compiled by: Dr. Michael Gaffney, Teagasc Ashtown, Ashtown, Dublin 15 T: 087 1205840 Email: Michael.Gaffney@Teagasc.ie Twitter: @Mick_Gaffney. Please contact Dr.Gaffney for further information.

 

Pest update – Week 20(2017)

(May 15th – May 21st) Compiled by: Michael Gaffney 

This week saw another large increase in the number of winged Aphids appearing in water traps. Both Carrot-Willow Aphids (Cavariella aegopodii) and Cabbage Aphids (Brevicoryne brassicae) have been recovered from water traps in brassica crops in Dublin and Kilkenny this week, in high numbers. Unsprayed Brassica and Carrot crops in Dublin and Kilkenny had large numbers of aphids present, with 50% of carrots at 2TL stage having aphids present. Large numbers of Cabbage aphids were present and reproducing on unsprayed brassicas in Dublin and Kilkenny. Some Macrosiphum euphorbiae (Potato Aphid) were also recovered in water traps in Dublin and Kilkenny.

First generation Cabbage root fly activity seems to be decreasing, with egg laying decreasing from 12 eggs per plant in week 19 to 6.1 in week 20 in Dublin and 5.6 eggs per plant in week 19 in Kilkenny to 0.3 eggs per plant in week 20.

Carrot root flies continue to be active in both our Dublin and Kilkenny sites. Numbers of carrot root fly caught in a newly emerging crop (2TL stage) caught this week exceed the 2 Flies/Trap/Week threshold. Growers are advised to use yellow sticky traps to monitor the situation in their own crops.

Caterpillar eggs were observed on brassica crops in Dublin and Cork.

A single silver Y moth was recovered from a pheromone trap in Kinsealy this week. To date, no diamond back moths have been observed in traps or within monitor crops. Flea beetles have been found in high numbers in both Dublin and Kilkenny causing damage on new transplants.

Fruit Pests

Spotted wing Drosophila activity has now been observed at several locations with individuals now being caught in traps within crops. Growers should be vigilant and continue to monitor crops and implement strict hygiene practices when harvesting crops. If not already doing so, growers should commence monitoring immediately.

The number of Light apple brown moth have been caught in traps in Dublin this week increased to an average of 42, increasing from the 27 caught last week. The number trapped at Kildalton this week (8.5) is similar to those caught last week (7). There are reports of tortrix leaf rolling damage in foliage, tree and ornamental crops becoming more obvious.

Beneficial Insects

Beneficial predators and parasitoids remain very abundant in crops. Growers should apply best IPM practices to preserve and maintain these populations. Several mummified aphids were observed in field vegetable crops this week.

Further Information and Samples to: Dr Michael Gaffney, Teagasc Ashtown, Ashtown, Dublin 15

T: 0871205840 E: Michael.Gaffney@Teagasc.ie Twitter: @Mick_Gaffney

Pest update – Week 19(2017)

(May 8th – May 14th) Compiled by: Michael Gaffney

Field Vegetable Pests

This week saw another increase in the number of winged Aphids appearing in water traps. Both Carrot-Willow Aphids (Cavariella aegopodii) and Cabbage Aphids (Brevicoryne brassicae) have been recovered from water traps in brassica crops in Dublin this week. A single Myzus persicae (Peach-Potato Aphid) and Macrosiphum euphorbiae (Potato Aphid) were also recovered.

Cabbage root flies have been active for the past 8 weeks and egg laying commenced 6 weeks ago in Dublin, with a large increase in egg laying in week 15. This level of egg laying has continued, with egg counts in a newly planted broccoli crop remaining increasing from 1.8 eggs per plant in Week 18 to 12 eggs per plant this week. Egg laying is now underway at Kildalton college, where approx. 6.8 eggs per plant were laid this week. Counts from our overwintered plots do not suggest that egg laying has reduced significantly in the last 3 weeks.

Carrot root flies continue to be extremely active in our overwintered plot. The prolonged dry spell has delayed emergence in newly drilled plots, although this week’s rain should ring them along.

A single silver Y moth was recovered from a pheromone trap in Kinsealy this week. To date, no diamond back moths have been observed in traps or within monitor crops. Flea beetles and brassica seed weevils continue to be active in an overwintered brassica plot and are being found in water traps.

Fruit Pests

Spotted wing Drosophila activity has now been observed at locations in Dublin and Wexford, with individuals now being caught in traps within crops. Growers should be vigilant and continue to monitor crops and implement strict hygiene practices when harvesting crops. If not already doing so, growers should commence monitoring immediately.

A sample of severe Leafhopper damage to strawberry foliage was received this week. Damage was obvious, with silver patches appearing on the leaf. It could be mistaken for early RSM or even thrip damage.

A significant number of Light apple brown moth (27) have been caught in traps in Dublin this week with some also being trapped at Kildalton (7). There are reports of leaf rolling damage in foliage and ornamental crops becoming more obvious.

Vine weevil pupae are very obvious in the soil / growth media at the moment. A useful guide to their control has been compiled by Donal Flanagan, Teagasc Nursery Stock Specialist.

A European Tarnished Plant bug (Lygus rugulipennis) was recovered this week, these capsids can cause severe leaf deformation on Viburnum and Laurel, so growers should monitor crops for any damage.

Beneficial Insects

Beneficial predators and parasitoids remain very abundant in crops. Growers should apply best IPM practices to preserve and maintain these populations.

Further Information and Samples to: Dr Michael Gaffney, Teagasc Ashtown, Ashtown, Dublin 15

T: 0871205840 E: Michael.Gaffney@Teagasc.ie Twitter: @Mick_Gaffney 

Pest update Week 17 (2017)

(April 24th – April 28th)

This week saw an increase in the number of winged Aphids appearing in water traps. Some winged Myzus persicae (Peach-Potato Aphid) were recovered from traps in Dublin, as well as Macrosiphum euphorbiae (Potato Aphid). No cabbage aphids or carrot willow aphids were found in traps.

Cabbage root flies have been active for the past 6 weeks and egg laying commenced 4 weeks ago in Dublin, with a large increase in egg laying in week 15, which has increased again in week 16 in an overwintered cabbage crop (Eggs in Week 15 34.3, increasing to 51.2 in week 16). Egg laying has commenced in a newly planted Broccoli plot in Dublin (2.1 eggs per plant). In 2016, peak first generation egg laying occurred in Dublin and Kilkenny in the third week of May. Current counts suggest that peak egg laying may be one to two weeks earlier in 2017, however this is very dependent on temperature. Active adult flies have been caught in both sticky and water traps since March in Dublin and a significant increase in adult activity in Kildalton was observed this week.

Carrot root flies have also been active with large numbers being detected in an untreated overwintered carrot plot in Dublin for the last 2 weeks. It will take a number of weeks for these flies to sexually mature and commence egg laying, however an average of 108 individuals were recorded in an untreated overwintered carrot plot in week 15, and this has fallen to an average of 62 in week 16. Females require time to mate and mature before egg laying, but a spell of good weather can increase the speed of this development. New observation plots were recently drilled and are beginning to emerge.

No silver Y moths or diamond back moths have been observed in traps or within monitor crops. Flea beetles and brassica seed weevils continue to be active in an overwintered brassica plot and are being found in water traps.

Fruit Pests

Spotted wing Drosophila activity has now been observed at 3 Dublin locations in week 17. In 2016, early season activity was not observed until Late May. This may be due to the mild spring, but most likely its due to an increase in the pest population. Growers should commence monitoring immediately.

A sharp increase in the numbers of Light apple brown moth have been caught in traps this week, (31) over previous weeks in Dublin, with some also being trapped at Kildalton (4).

Beneficial Insects

There was a noticeable increase in the number of parasitoids, both wasps and rove beetles active within crops this week. Growers should apply best IPM practices to maintain these populations.

Further Information and Samples to: Dr Michael Gaffney, Teagasc Ashtown, Ashtown, Dublin 15

T: 0871205840 E: Michael.Gaffney@Teagasc.ie Twitter: @Mick_Gaffney

Pest update – Week 16 (2017)

(April 17th – April 23rd)

Cabbage root flies have been active for the past 5 weeks and egg laying commenced 3 weeks ago in Dublin, with a large increase in egg laying observed this week. The number of eggs per plant recovered increased from an average of 3.6 per plant in week 15 to 34.3 eggs per plant this week. In 2016, peak first generation egg laying occurred in Dublin and Kilkenny in the third week of May. Current counts suggest that peak egg laying may be one to two weeks earlier in 2017, however this is very dependent on temperature. Active adult flies have been caught in both sticky and water traps since March.

Carrot root flies have also been active with large numbers being detected in an untreated overwintered carrot plot in Dublin. It will take a number of weeks for these flies to sexually mature and commence egg laying, however average numbers of 2.3, 1.75 and 2.6 flies per yellow sticky trap were observed in Dublin for weeks 12, 13 and 14. New observation plots were drilled this week and will be used to monitor for adult activity and egg laying. Females require time to mate and mature before egg laying, but a spell of good weather can increase the speed of this development.

To date no Aphid pests of concern have been caught in water traps or sticky traps or observed on crops. No silver Y moths or diamond back moths have been observed in traps or within monitor crops.

Flea beetles and brassica weevils have been active in an overwintered brassica plot and are being found in water traps. Also found were some Scaptomyza flava individuals, which is a fruit fly whose larvae can cause mining damage, particulary in brassica baby leaf products.

Fruit Pests

Spotted wing Drosophila activity has now been observed at 2 Dublin locations in week 15. In 2016, early season activity was not observed until Late May. This may be due to the mild spring, but most likely its due to an increase in the pest population. Growers should commence monitoring immediately.

Low numbers of light apple brown moth have been caught over the last fortnight, which may indicate the emergence of the first generation of this pest.

Further Information and Samples to: Dr Michael Gaffney, Teagasc Ashtown, Ashtown, Dublin 15

T: 0871205840 E: Michael.Gaffney@Teagasc.ie Twitter: @Mick_Gaffney