European Chafer

I have moved to a house in New Westminster where there is an infestation of the European Chafer and I am new to gardening.

Our lawn does looks fairly healthy compared to some neighbouring lawns that have larger brown patches and many more divets from skunks.

So far I've seen only a couple of grubs in our yard, but I'm wondering what special care my lawn I will need this season to avoid a serious problem .

Our lawn seems green and healthy, but also "lumpy" and "loose".

I have read some stuff on controlling chafers. I am not clear if pesticide is needed and how effective it would be anyway. (I'd sure like to avoid having to use it.) What should I be doing when given our climate on the coast?

 

It sounds like your lawn is not colonized with Chafers yet. The Ministry of Agriculture feel control is only warranted when there are more than 20 grubs found in a 30 by 30cm piece of sod to a depth of 5 cm. Maintaining a healthy lawn would be the prudent approach at this point. The grubs are most damaging in the fall and early spring, however the typical brown patches can be masked by heavy rainfall or irrigation during these times. Lawn damage is often worsened by the skunks so keep your lawn healthy so they won't be tempted. Our mandate at UBC is to recommend sustainable practices without the use of pesticides.

 

European chafer is a serious problem in New Westminster and soon will be throughout the Lower Mainland. While the damage caused by these insects is considerable--large brown patches in turf--the damage caused by skunks searching for chafer grubs is significantly greater. Some have likened the activities of skunks on lawns to attacks by rogue rotovators.

The life cycle of the European chafer is outlined in a Ministry of Agriculture, Fisheries and Food factsheet, which is found by clicking here . Because the grubs feed throughout the fall and winter, and pupate in April, they are most susceptible to control in late winter.

For control of established populations, try flooding affected areas with water periodically in February and March (only when temperatures are well above freezing). This will bring the fattened grubs to the surface, where they are easy prey for birds, such as European starlings and crows (birds do considerably less damage than skunks and are effective grub eaters). To encourage birds, curtail outdoor activities and abrupt noises and make sure cats are kept indoors where possible.

According to researchers at Michigan State University, grub feeding is more pronounced in dry soil conditions relative to wet, suggesting that unirrigated lawns are at greater risk. Perhaps adult egg-laying site preference can be used as a control strategy. That is, by watering when adults are laying (usually in May and June) they will be discouraged from laying in your lawn.

Feeding preferences for the European chafer are not well known. Unhealthy turf that is heavy with thatch may be attractive to grubs; then again, a healthy, velvety sward may be the ideal winter pasture from the insect's point of view. Look around the neighbourhood. If most of the damage is in lawns that are already pretty neglected, there's your answer (and let us know).

 

I would like to add my observations to this as I have been quite adversely affected by this pest in the last 3 years.( live in New West)
I tend to take care of my lawn ( aerate, add lime, sand yearly - dethatch bi-annually and water up to the max allowed by GVRD, try to stay away from pesticides now) I even put sprinklers in last year on the boulevard as it tended to dry up in the summer.
Three years ago was my first inkling there was a problem but of course I had no idea what it was. Biggest damage was done by the raccoons digging for food ( and still is)
Two years ago I could see what was causing the problem but still didn't know what it was but knew the grub was the problem
Last year I was out in the yard about 9:30 at night in June when I heard a sound I've never heard before. It sounded like miniature helicopters hovering around my deciduous trees in the backyard. ( bing cherrry and magnolia)
That's when I made the connection that this thing is the cause of my grief.
Unfortunately I didn't have my can of RAID. ( I will next June though)

As for the theories of keeping a health lawn as a deterrant, I don't believe that is a valid argument. I have 2 neighbours that do no yard maintenance at all ( ok one mows his lawn but the other is an absolute dandelion factory) and they have not been affected at all. I'm talking no adverse affects at all because I have been watching in utter amazement.

Although one has deciduous trees on the boulevard and a big deciduous tree in the year, the other one has none.

I believe that getting them when they are mating in the trees is the key (obviously uneducated guess) so next June I will be out there with my spray bomb ready for the mating dance.

All I have read about these things suggest nothing else is a sure thing.

I can keep you posted if you would like.

Mike

 

European Chafer in BC

I too live in New West, and I really don't know what the fuss is all about, so long as you're willing to use traditional (i.e. chemical) lawn care. I'd prefer not to, but have chosen the traditional route because the "natural" way appears to be a failure, from what I can see.

I'm in the west end of the city, and two summers ago my lawn was badly damaged by skunks and crows digging up the little morsels. Large parts of the lawn also died off.

Last summer I was prepared. I applied one bottle of Sevin to the turf in late July (available at Mandevilles and Home Depot), and again about 2 weeks later in mid-August to all my lawns. No problem this year. My lawn is back to its normal condition, meanwhile my next door neighbours' "natural" lawns looks like Hiroshima.

What irks me most is that the "politically correct" city parks people won't even tell you there is a straightforward method to control this terrible pest. I had to rely on the wise advice of the people at Mandevilles. I think the natural lawns are doomed in this area.

Martin

 

Heterorhabditis bacteriophora

Heterorhabditis bacteriophora may be used to treat chafers. I don't know if these beneficial nematodes are avialiable for sale in Canada.

 

Mr.

The time for pesticides, when the grub 1st appeared in the city, has passed.
You may stop them in your yard, but the Lower Mainland had best prepare for a Beetle Invasion. And how many birds will die for no net long term benefit.
My lawn is fine. I pull weeds and water occassionally, but that's it. My neighbor's lawn (poorly maintained) was devistated. My other neighbor's lawn (incredibly well maintained) was also devistated.
I believe this is the solution:
Underground barriers.
My lawns are islands of grass surrounded by either concrete walls, sidewalks or treated timber ties. I suspect the grubs stay close to the surface and won't go under these barriers therefore allowing the home owner to contain them.
One small section of lawn my die, but it can be repaired after the beetles take flight.
Also my kids love to catch them. They put them in a jar and they're dead within a couple of days. Then we flush them down the toilet.
How about the putting a bounty on them during the mating phase? 5 cents a pop. Industrious kids could make killing!

 

Strange reading, this. They are native here, but while the old agricultural books of 50 years ago record them as a serious pest, they are now very rare and declining (I've seen just one in my whole life). They just can't cope with modern agriculture.

It would be nice if they could all be repatriated. Our birds need them.

 

there is another thread here on this subject. Nemotodes are not available in Canada at this time, although I don't understand why -- import restrictions? I also understand that public areas are first to get them when the do become available (next year?) and individuals will follow comercial. To be honest, and from a theoretical point of view skunks are natural controls, but from a gardner, having your yard nuked by skunks isn't. I can't remember who, but someone on these forums is rather close to and up to date on the problems or you might try finding that thread.

 

Ok! I too live in New Westminster, but I gave up the fight. We had the entire front lawn removed and had it landscaped with native plants, grasses and perenials. This was a costly however amazing solution. We are thrilled with the results. This, however has resulted in a whole new obsession-gardening! Hence my appearance on this board as I know little about the whole procedure but am already planning next spring's addition to my garden.

 

European chafer is running rampant in my section of town, East Van. Are there any new developments for dealing with them?

 

nope.
Merit (amidicloprid) or nematodes are two spray controls. Turf management to provide optimal growth conditions is another (or an accompanying) method and, turfgrass replacement with non turfgrass (clover) is another.

and along the lines of this...
http://www.horteducationbc.com/Biocontrol.pdf

 

How do you get them to survive?

They are effectively extinct here where they are native.

 

Cheeky!

:)

it seems that the native nematode population is too low to eradicate them, the skunks, crows and racoons are trying to keep up but so far, their westward movement is unimpeded. maybe they will keep going west and follow the lemmings in to the ocean?

 

Actually, it's a pretty serious biodiversity disaster - several birds used to depend largely on chafers as a food resource. Notably, the Red-backed Shrike is now extinct as a breeding bird in Britain, and several other birds that feed on large insects (most of which are also in steep decline) have become a lot scarcer.

 

interesting. the major feeding beasts here are the crows, then skunks and raccoons.

 

I heard of a dangerous aspect to grub damage...a homeowner had a long rather steep slope of grass. While mowing it on his riding mower, an entire section of grass under the mower simply gave way. He, riding mower, and the piece of lawn slid out of control to the bottom of the bank. Apparently grubs had eaten the roots, yet the piece was still green. He said the loose section resembled a large piece of sod freshly cut from a turf farm.

 

My lawn is being rototilled at an astonishing rate (the edge of the disturbed lawn moved about 5-10 feet overnight the other day) by a local skunk.

I don't want to use chemicals (both for my family and for the environment and the fish), so I am looking at alternatives to grass.

Is the there an Open House of gardens where people have done this, so I could get some ideas and experience from normal folks who took the plunge? Who would organize such a thing?

Thanks in advance for ideas.

Chris.

 

hello chris

here is a link to good information about the chafer

http://www.nwpr.bc.ca/parks web page/chafer work.html

essentially if you let the skunks and racoons eat as many of the chafer larvae as they can. the larvae then will not become adults and we have broken the life cycle.

nematodes are the safe option as they are predators of the larve and they are applied in late july. they are available from several garden centres including gardenworks in Burnaby

I hope this is of some help

 

Much of the work cited in the link above was done by Debbie Henderson of ES Crop Consultants. They work in the Lower Mainland.

 

Thanks, Pierrot,

I guess I should have included more information. I have read quite a bit on-line, and last year, at the appropriate time, I purchased and applied nematodes to the part of my lawn that was dug up last year.

However, last year it was mostly crows, and the divets were comparatively small (crow-beak sized :-) ). This year, after the crows slowed down, a skunk moved in (we've seen him/her in action, so we know who it is) and has been systematically destroying the lawn. Something like 80% of the lawn has been dug up. The turf roots are completely severed; I can rake up the sod and expose bare ground without any digging.

I don't really *like* grass anyway, and certainly not enough to invest what it seems to take to have a "healthy lawn". So, I'm ready to look at alternative ground coverings and getting rid of grass altogether.

Since I posted last week, I have obtained some Dutch white clover seed, and seeded a small sloped part of my lawn that was already pretty bare.

I still think it would be useful for there to be an "open house" for people to view examples of gardens where the owners have replaced the grass with alternative lawn cover. I'm going to be visiting the local Gardenworks on the weekend of March 17-18 to get information and ideas.

Chris.

 

a lawn we replaced last year (New West). seeded in april I think.

 

Right. So if we let the crows become completely dependent on the chafers, and the chafer expansion keeps going west and thus eventually runs out of territory, there might be some hope that crows will become extinct!!

I know, I know, only if people could get out of the habit of producing garbage. Too bad crows are such adaptable creatures.

 

Thanks JimmyQ, it looks like that replacement looks a lot better than the original.

And, to Karen, non-lover of crows - my Ontario relatives are nostalgic about our crows when they visit because West Nile Virus has killed about 95% of them back east. I'm sure it will get here soon, and we will have many fewer birds.

Chris.

 

West Nile has already been out here awhile and is killing birds.