Tony Dickerson problem solves
QWhat is this large slug that I found in my garden? Mr E Hughes, Stafford
ALarge, impressive, pale slugs with prominent darker stripes or mottling are most likely to be leopard slugs ( Limax maximus). They originate from southern Europe, but are now widespread in the UK.
Most slugs are short-lived, rarely surviving a season, but veteran leopard slugs may reach almost three years of age and grow to nearly 15cm (6in) in length. The pattern of stripes and spotting can be very variable. The ash-black or ash-grey slug ( Limax cinereoniger) is similar, but grows to 25cm (10in) and is, generally, a woodland species. There are some 44 species of slugs in the UK and most, such as the leopard slug, feed on decaying vegetable matter so are useful in the garden and compost heap. The leopard slug is also partially carnivorous and may prey on other slugs, so it’s actually quite helpful in the garden. It’s the smaller slugs, such as the grey field slug, that damage foliage, while keel slugs in the soil tunnel into potatoes and other tubers. Now’s an ideal time to get on top of troublesome slugs. Simply keeping the garden well cultivated with regular forking and hoeing will help enormously. Mulches of compost or well
rotted manure are better than bark because there are fewer nooks and crannies to hide away in.
Biological control is perhaps the most environmentallyfriendly option, but you’ll need five or six applications of nematodes to give full control over the season. This can prove quite costly, but a single application now will go a considerable way to reduce breeding populations for the rest of the summer, especially as the mild winter has seen record numbers of slugs overwintering.
If you use pellets, choose ones based on ferrous phosphate, which pose less of a danger to wildlife. Apply just a dozen or two to a square metre and top up when they disappear. Great piles of pellets offer no more control and, once damp, they quickly spoil.
Some gardeners put their faith in creating barriers to prevent the passage of slugs, but I feel this is largely an exercise of optimism over reality!