From the Garden: Two Classic Garden Pests -Slugs and Aphids

By Erin Breglia

Slugs! Aphids! The names alone bring a creepy-crawly feel­ing to mind, espe­cial­ly if these pests have been sab­o­tag­ing your gar­den! But rest assured, if we uti­lize appro­pri­ate ways to dis­cour­age them and under­stand the ben­e­fits they pro­vide in our envi­ron­ment, we can find ways to live togeth­er with­out bug­ging each other!

The slug is a soft-bod­ied mol­lusk rather than an insect. Its clump-like body moves along on its foot, and it secretes an ooz­ing trail when it moves. Unlike the sea mol­lusk, the slug does not require a shell for pro­tec­tion. Slugs must always stay moist to sur­vive so they love wet, dark areas. They can be found under­neath sur­faces, hid­ing in large wood chip mulch or at the base of plants. They are active at night so it can be dif­fi­cult to know if they are dam­ag­ing the gar­den. A quick trap of lay­ing card­board on bare ground around the base of plants and turn­ing it over each morn­ing to see if they have accu­mu­lat­ed can help. Scrap­ing the slugs off and remov­ing them from your gar­den can offer con­trol. The trap can be reset until the prob­lem sub­sides. Oth­er options include the appli­ca­tion of diatoma­ceous earth or crushed oys­ter shells around the base of plants. Both dam­age the soft body of the slug and will also deter them from enter­ing the area.

Aphids are anoth­er nui­sance that can wreak hav­oc in the gar­den. These true bugs have straw-like mouth­parts that they use to pierce and suck the flu­ids from plant leaves and flow­ers. Most abun­dant in spring, they can rapid­ly repro­duce and col­o­nize a plant, with the adult life cycle aver­ag­ing one month. They favor all sorts of plants and dam­age them very quick­ly, but as sum­mer tem­per­a­tures rise, their pop­u­la­tion decreas­es. The best way to con­trol them is to use a nat­ur­al insec­ti­ci­dal soap spray called Safer Soap. This solu­tion will con­trol aphids by pen­e­trat­ing their out­er lay­er and dry­ing them out with­out dam­ag­ing the plant or ben­e­fi­cial insects which feast on them as well.

Though slugs and aphids may look off-putting, they do offer ben­e­fits to the gar­den that should not be over­looked. Slugs are a food source for toads and birds and also cre­ate aer­a­tion in soils when tun­nel­ing. Aphids are an excel­lent food source for ben­e­fi­cial insects in the gar­den such as lady­bird bee­tles and lacewings. They also have an inter­est­ing rela­tion­ship with ants, which will pro­tect them from preda­tors in exchange for the sweet excre­tion they pro­duce called honeydew.

These rhythms of nature are in place to con­trol pop­u­la­tions and until out of bal­ance, things should be man­age­able. If envi­ron­men­tal fac­tors such as an abnor­mal abun­dance of rain occur, both of these pop­u­la­tions are like­ly to increase, but with some nat­ur­al prod­ucts and preda­tors and a lit­tle extra atten­tion a gar­den­er can rebal­ance the wheel with min­i­mal dam­age to the environment.


Summer 2018

Volume 36 , Number 3

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