The Scarboro Garden Scene – Lily Beetle Warfare
Just when you have found the perfect plant for August, you find it has an arch enemy: over the last decade or so, Asiatic and Oriental Lilies have become readily available in a huge range of colours, and are wonderful to behold. Also very striking is the beetle you may find with them, but check the City of Calgary website to identify the scarlet “guy” eating great holes in your lily leaves and leaving only an upper membrane: the Lily Leaf or Red Lily Beetle, with the generic and specific name Lilioceris lilii, came to Calgary in 2009. Apparently it was first seen in North America in Quebec in 1943, and had moved westwards to Ottawa by 1981.
Fortunately, once you have seen them, you can easily pick them off and kill them – no chemicals used here – although the larvae could probably be handled that way. The City recommends sprinkling diatomaceous earth on them to produce dehydrating abrasions (as it does on slugs): they overwinter in the soil, so be vigilant in the spring and you will be able to control them. Although they their preferred host plants are lilies, they also like fritillaries (and Lily of the Valley provide food for the larvae). One characteristic they have is if they are knocked off a lily, they fall upside down on the ground, and their black undersides are very difficult to see against the colour of the soil. The adults are longer than lady-beetles (lady birds) with a rectangular body shape, about 7 mm (1/4 ”) long.Reader viewer discretion suggested here…. the larvae disguise themselves with their own dark faeces that look like bird droppings, and the adults rub body parts together (“stridulate” – a lovely word for extra points in scrabble). Now - back to spotting the little nuisances while they are still on the lily leaves.
Glynn Wright 403-680-8289
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