Sunday, March 20, 2016

Grubmageddon

Welcome to Spring, but before we get too giddy let us address, what potentially, could be a nasty year for insects. The two most prevalent culprits causing damage to lawns in southwestern Ontario are Hairy Chinch Bugs and White Grubs.  We could be in for a rough ride from both this year.

Chinch have been invasive over the last few years and 2016 promises no different, but we will deal with that issue when we get into June. For now, my main concern  is grubs and that will be the focus here.
Grubs have been relatively quiet the past three years which means the cycle is coming to an end and a period of three years of increasing numbers is evident.
There are a few factors to consider; the first being the mild winter we experienced. Grubs over-winter and when temperatures are more on the mild side grub populations easily remain intact.
There were signs of excessive digging activity in areas north of the G.T.A. last fall suggesting greater numbers and since this is a migratory insect, look for invasions to lawns further south this year. Also, let me not forget my suppliers who all touted white grub on the increase as the 2015 season came to a close.

                At first glance, symptoms of White Grubs and Chinch Bugs are similar.  Both cause irregularly shaped yellow to brown patches in the lawn.  But if we examine the issue carefully, it is quite easy to detect the difference between the two.

                White Grubs do most of their damage in early spring and in fall.  The adults, Japanese Beetles, resemble June bugs but are smaller, more slender and have shiny copper coloured wings.  The adults don’t damage grass, but feed voraciously on many plants, trees, perennials.  They do most of their eating in July and August.
                  Beginning in late July to mid August, adult Japanese Beetles lay eggs which hatch in a few weeks.  The eggs become tiny White Grubs with quite an appetite.  They eat grass roots causing irregularly shaped dead patches.  Damage is minimal when the grubs are tiny, but as they mature later in the fall, damage can be quite extensive.
I'm not saying all this to sell grub and insect packages it is simply the truth we live with in the here and now. Organic means are not as effective as traditional methods and there is always going to be fallout.

                 When weather becomes cool, White Grubs go deep into the soil.  In spring the grubs emerge and begin feeding again.  When the grubs are fully grown they transforms into adults and the process repeats itself.

                To control White Grubs and the subsequent Japanese Beetles, apply nematodes which are tiny naturally found organisms that feed on the grubs.  Ideally, nemetodes should be applied beginning late summer to early fall, when the grubs are small.   Add at least 3 inches of water  to the lawn before and after application so the nemetodes have the ability to travel through the soil.

If you are looking for an alternative to nematodes in Ontario, there isn't any. Such is the reality of our surroundings with limited controls and treatments at our disposal.

                 The best defense against all insects is a healthy lawn.  Start with good soil. Fertilize faithfully to keep the grass growing.  Water during dry spells.  Mow regularly and punctually, and don’t cut the grass too short.

                  As lawn care becomes more challenging, rejuvenating the lawn makes more sense.  If your lawn is weak, dying or dead, apply a layer of top dressing topsoil and sow a good quality grass seed.  The best time to apply grass seed is late summer and fall.
Don't play Russian Roulette when it comes to your grass, especially during a grub apocalypse.
You may dodge the bullet in the chamber for this season, but sooner or later luck runs out and your lawn will suffer.