What's Buzzin'.....? Newsletter

SLUGS AND SNAILS TOP OF RHS PEST LIST AGAIN IN 2009

Slugs and snails were the UK’s most troublesome garden pest of 2009, according to members of the Royal Horticultural Society (RHS). These slimy plant predators moved one place up in the ‘league table’ on last year, just beating the recently established Harlequin Ladybird into second place.

The COOL summer of 2009 played a big part in bringing slugs and snails into people’s gardens, where they wreaked havoc among the foliage and flowers of established plants and killed seedlings along the way.

Second place in the RHS Top 10 went to the highly publicised Harlequin Ladybird, which became established in south east England in 2004 though they have spread to most parts of England and Wales. The Harlequin Ladybird has a voracious appetite and both the adults and larvae eat aphids and other insects, including beneficial predators, such as native species of ladybirds, hoverfly larvae and lacewings.

(See our Slug and Snail control products including programmed deliveries of Nemaslug®)

Top 10 Pests 2009

• 1. Slugs and snails (various species)
• 2. Harlequin ladybird (Harmonia axyridis)
• 3. Lily beetle (Lilioceris lilii)

• 4. Vine weevil (Otiorhynchus sulcatus)
• 5. Chafer grubs (various species)
• 6. Viburnum beetle (Pyrrhalta viburni)
• 7. Pear leaf blister mite (Eriophyes pyri)
• 8= Ants (mostly Formica and Lasius spp. )
• 8= Rabbits (Oryctolagus cuniculus) - see our newly added "GRAZERS" Rabbit/Deer and Pigeon deterrent)
• 10. Capsid bugs (Lygocoris pabulinus and other species)

©RHS

Visit our Bio-controls for solutions to these pests

Create a pest barrier

Temperatures should now be moving up and so will the number of potential pest problems (as the above would seem to prove). One solution to help with pest control is to place physical barriers in their way. One could use a tent of fine mesh over the plants (see Wondermesh® barrier) – this might not look attractive but it is a useful preventative mechanism. For slugs and snails try SnailAway™ barrier.

WHAT TO WATCH OUT FOR THIS MONTH

Slugs and Snails

As the temperature starts to increase, slugs are everywhere from this month and controlling them can be a real task. Trapping them will reduce the numbers significantly and there are several methods available (see our slug trap products). Now that soil temperatures are rising another, effective way of getting rid of these pests is to apply Nemasys Slug Control. These nematodes can be watered or sprayed around plants onto moist soil. The nematodes search out and infect slugs killing them below ground where they hide.

Fruit moths

You won’t often see the moths attacking your apples and other fruits but you may well have found their offspring buried inside the fruits! One solution is to use pheromone lures in Delta traps to attract the mail moths to a sticky end. If there are no male moths around the females can’t mate and there’ll be no offspring/no maggots. How does it work? A small plastic container with the pheromone is placed inside the Delta Trap, the female pheromone “scent” (which is specific to the particular pest) to attract the male is slowly released and when the male moths fly into the trap they are caught on a sticky insert. The lure and the sticky trap can be replaced regularly to keep the Delta Trap working effectively. We have extended our range of taps and lures for the 2010 growing season.

Gooseberry Saw Fly caterpillar like larvae, which will eat leaves until there is only the skeletal midribs left. You can rub the pests off by hand when they’re small or use a strong jet of water to wash them off (Solomon’s Seal Sawfly can be dealt with in the same way). Or, of course there are several bio-solutions such as Nemasys Caterpillar Killer, (the new) Nemasys Grow Your Own aas well as NeemRepel and PestOff.

Cabbage Root Fly you could use a tent of fine mesh over the plants (see Wondermesh® barrier) or collars of card or similar material around the stems of brassicas such as cabbage and broccoli. These act as a physical barrier (see above) to prevent the flies from moving down the plant stem to lay eggs in the soil.

DERRIS & AMCIDE TO BE BANNED

The European Union pesticides review started in 1996 aims to ensure that substances used in pesticides meet the most modern standards of human and environmental safety. For products to achieve approval producers must supply data to prove that they meet EU criteria. This is a very costly process and with some products the producers are no longer prepared to pay for this and as a result several controls previously available to organic growers will no longer be available.

Under the review, two pest control materials used by organic gardeners – the pesticide ‘DERRIS’ (rotenone) and the stump killer ‘AMCIDE’ (ammonium sulphamate) are to withdrawn.

’AMCIDE’ was withdrawn from sale in 2007 and cannot legally be used (or kept in store!). Retailers will probably have until September of this year (2008) to sell their remaining stocks of ‘DERRIS’ (though the UK has been granted ‘Essential Uses’ for professional users for apple, pear, peach, cherry, ornamentals and potato). Fortunately, there are a number or alternative methods of control available to the organic gardener - see our biological controls section.

EXPERTS WARN OF CHEMICAL CONTROL RESISTANT CODLING MOTH

Insect experts claim that the risk of Codling Moth becoming resistant to the main insecticide chemical groups is increasing as global arming takes hold. The pest favours warm conditions and over last ten years its second generation (August) has been getting stronger and is much more damaging than the first (June). The pest has already become a big problem in central and southern Europe’s apple growing areas, making more frequent spraying necessary.

If the pest becomes resistant to chemical control apple growers will have serious crop problems. However, there are several alternatives to chemical control. As well as pheromone lures (very effective against low moth populations) there is a new entomopathogenic nematode is available (see Nemasys® Caterpillar Control).

BEETLE COULD BE THREAT TO BRASSICA CROPS

Leading insect expert Dr Rosemary Collier has warned growers that a pollen beetle resistant to pyrethoids controls – a pesticide that has been used by growers for more than 20years – could spread to UK brassicas from rape crops. The first beetles were detected in the UK in 2006 and by 2007 had spread to most coastal areas of East Anglia and the South.

This year they could spread to other parts of the country.

Dr Collier advised growers to keep evaluating non-insecticidal alternatives such as physical barriers (see Wondermesh® barrier).

KOPPERT DEVELOPS BIOPESTICIDE TO TREAT POWDERY MILDEW

Salad and strawberry growers are set to benefit from a new biopesticide developed for powdery mildew control according to Dutch biological pest control specialist Koppert. It has been approved in Holland and its Pesticides Safety Directorate registration is being sought initially for strawberries and salads and eventually all crops on which powdery mildew is a threat. The product is based on the enzyme lactoperoxidase that occurs in milk, saliva and tears. In trials it outperformed conventional fungicides against powdery mildew. The product is not yet available to home and allotment gardeners.

MORE FUCHSIA GALL MITE DISCOVERED IN THE SOUTH EAST

Since the first discovery of the fuchsia gall mite in mainland Britain at a single location in September last year, the pest has been found at two more locations.

The arrival of the mite (Aculops fuchsiae) was discovered when infected plant material was sent to the RHS advisory service by a gardener in Fareham, Hampshire. The pest is currently being controlled under the current policy of destroying infected plants, but there might come a time when the pest would be beyond practical control because it can be dispersed by winds. The mite can be killed at temperatures below 5°C but evidence on the pest in Brittany suggests it will be able to overwinter within the buds of a Fuchsia plant in the UK. The public should not bring Fuchsia cuttings into the country as it is suspected the pest was introduced on plant material from Brittany.

To view the updated pest notice go to www.defra.gov.uk/planth/pestnote/fuchsia.pdf. Suspected outbreaks should be reported immediately to the local DEFRA Plant Health & Seeds Inspectorate (PHSI) office or to the PHSI HQ in York 01904 455174.