Controlling Lawn Grubs Organically
tangency Arzeena HamirBeetle grubs can wrench a fine look lawn into a jumble quilt of yellow spot . But before you contact for the insecticide bottle , there are a number of constitutional alternatives that will help you cope with the grubs without poisoning yourself or your family .
What are these grubs ?
The eats that you see in the lawn are the larvae of Japanese beetles , June beetles , and chafers . These grubs are C - shaped , off - white in color with a dark forefront . They eat on the roots of grass , causing the Gunter Grass to die and forge brown patch . lawn that are heavily damage by grubs will have a yellowish tinge and will palpate spongy when walked on . The sod itself can be easily lifted , a sure sign of the zodiac that the brown patches were not have by dog piddle .
living cycle
Adult beetles come forth , mate , and lay ball from late June until other August . The egg hatch in about two weeks and the tiny grubs grow quickly . The yellowing patches of greensward usually appear in late August and September , when the grubs are vigorously feeding and the sward is otherwise water - stressed . In October or November , when stain temperatures start to cool , the grubs contain feeding and move deeper into the soil , where they spend the winter . They return to the root geographical zone and resume feeding early on the undermentioned leap .
What to do
Just a twosome grubs per square foot are not a problem to an otherwise healthy lawn . Ten or more per satisfying foot are necessary to excuse intervention . Predatory roundworm are available for use in Canada and the US as a biological ascendance for white grub . The role of these nematodes requires that the soil be kept very damp and it is very important that the app instructions for this product be followed closely , as nematodes are living organisms .
cover the entire lawn . Do not attempt to operate lawn pest by spot applications . Water the lawn thoroughly after applications programme to wash in the nematode worm .
When to handle the lawn ?
The younger the grubs are , the prosperous they are to ensure . The best prison term to use chow control touchstone is from mid - July to August and September when the grubs are small and near the soil aerofoil . Although treatments can be made after this time , grubs will be more unmanageable to kill ( because of their larger size of it ) . The second best time is March to April when the grubs are once again near the stain aerofoil but a niggling larger .
advance natural enemies
Certain mintage of wasps parasitize blank eats . They are sometimes seen hovering over the turf in previous summer in search of green June beetle grub on which to lay their eggs . They are not aggressive and normally will not twinge people . The wasp larva feeds outwardly upon the grub , eventually kill its dupe before spinning a fuzzy , brown , jelly bean - size of it cocoon in the soil . Predators such as ground mallet and ants also take their toll on bollock and young snowy grubs .
wield your lawn to minimize terms
Lawns that are heavily managed and watered on a regular basis may actually attract beetles . They favour grassy areas where the soil is constantly dampish such as lawns , pastures , and meadow in close - cropped grass . Frequent irrigation in June and July may pull in egg - laying distaff beetles to the turf , specially if surrounding areas are dry .
In demarcation , equal dirt wet in August and September ( when grubs are actively feeding ) can help hide root injury . If grub damage starts to appear in late August or September , lachrymation will advance permissiveness and recovery . thick , periodic soaking of the turf is more beneficial than frequent , weak lachrymation .
Resources :
Terra Viva Organics Supplies predatory nematode worm on - line .
University of Florida Factsheet – Microbial Insecticides A gravid overview of the advantage and disadvantage of using nematodes , Bt , and other biological insecticide .
Ohio State FactSheet Good verbal description of grubs , dismiss the chemical advice
Arzeena Hamir is an agronomist and garden writer based in Vancouver , BC .
