Designing a Pond

Lessons Learned

I love almost everything about my little pond (about 10′ x 7′) but I certainly didn’t build it perfectly. There’s probably a reason people make their living creating ponds for people who can’t do it themselves…

Pond July 27 2016

Pond July 27 2016–with a leaning bird feeder in the foreground 

Mosquitos

Latest lesson is about water movement. Guess what? The movement of 1000 G per hour at one end of the 10′ pond is not enough to prevent stagnation at the other end of the 10′ pond. My neighbour casually mentioned they’d noticed more mosquitos lately and “did I think they could be propagating in the pond?” I assured her that tho’ I’d seen some larvae a while back, I was pretty sure the agitation from the waterfall was enough to prevent still water–which is what mosquitos want for egg-laying. Wrong! I peered into the edges of the pond and waited to see movement. Not only did I see a few  2-3mm black “commas” (that I’d seen before), but the longer I looked the more I could see ZILLIONS (ok, maybe not quite that many) of much smaller moving bits. Next day I was out buying goldfish!

Here is an excellent short article on preventing a mosquito explosion in your pond.

When the first “scoop” of 18 fishies seemed to be effective (fewer larger larvae), I went and got another 15. So far the racoons have either not noticed the fish or figured they were too hard to get. There are LOTS of nooks and crannies and hiding places in the pond, including two caves that I built even tho’ I was sure I didn’t want fish. I’d had too much racoon activity over the years to encourage even more devastation. But really, choosing between a mosquito infestation and potential West Nile virus, and a few cute furry (big) rodents–no contest!

Stay tuned for more Lessons Learned.

 

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Help, My Lawn Has Been Thrashed!

CHAFER BEETLE DAMAGE

Female chafers lay 20-40 eggs over their lifespan. They are laid singly, 5–10 centimetres (2.0–3.9 in) deep in moist soil, and take 2 weeks to hatch. The grubs hatch by late July. In frost zones, the grubs feed until November, then move deeper into the soil. In frost-free areas, the larva will feed all winter. Vigorous feeding occurs from March through May. In early June, the grubs again move deeper, from 5–25 centimetres (2.0–9.8 in), to form earthen cells and pupate. The pre-pupal and pupal stages last 2–4 days and 2 weeks, respectively. By June, the new beetles begin emerging. (Wikipedia)

Thanks Wikipedia.

Crow damage

Crow damage

If you live in Metro Vancouver you have seen this, probably in your own neighbourhood, and possibly in your own lawn. This is European Chafer Beetle damage, caused not only from the beetle grubs, but even more from the predators that feed on the grubs.

IMG_1051

Crow damage

The C-shaped really disgusting-looking grubs (how could anything called a “grub” be anything other than disgusting-looking?) started the damage by feeding on the roots of mostly turf. Some sources say they’ll feed on other vegetation roots if there’s a shortage of turf, but that doesn’t seem to be an issue yet, since we have lots of lawn. So you will seldom see this kind of damage in a lawn that is thick and green–it’ll have nice long roots preventing the animals and birds from pulling up the turf. You can see in the pictures that the undamaged areas still look pretty patchy. Of course, it is winter…

Then once the predators know the grubs are big enough to provide a tasty morsel, they start to dine–seems to be Fall through Spring. And since the grubs have already eaten away at the roots, the turf is now more like a carpet laid on the soil, so the crows, racoons and skunks don’t have to work very hard to get the turf out of their way.

Crows doing the damage.

Crows doing the damage.

More crows, more damage.

More crows, more damage.

 

Damage control

Damage control

Trying to keep the “carpet” pinned down will have limited success, since the critters can easily pick away in the spaces. Enlarge the above picture and you can see patchy areas that may have been damaged before the netting went down, or since.

Racoon damage

Racoon damage–just a little.

IMG_1056

Same site, different angle.

This was what I found one morning in early December. I’ve had crummy turf, but no CB damage for the 7 years I’ve been here, but since I wasn’t going out of my way to make my lawn really healthy (I keep vacillating on replacing it with…something), an infestation was inevitable–I was disappointed but certainly not surprised. Why racoon damage instead of crow damage? Who knows–I guess because there are racoon families in some of our neighbourhood Douglas-firs.

THIS did surprise me though.

Lots and LOTS of racoon damage.

Lots and LOTS of racoon damage.

Between waking up (in the dark) last Monday morning (I like to look out the front window while I’m brushing my teeth–sometimes I’ll see skunks or racoons ambling by) and leaving the house (in the dark) 45 minutes later, the racoons had had breakfast.

I guess I should be grateful to the racoons, not only have they probably decimated my chafer beetle population, they’ve also made me stop procrastinating making a new design for my front yard. I’m checking out Houzz “lawn alternatives” page.

PREVENT DAMAGE:

I’d like to see your lawn protected from this damage in the first place. We’ve got the invasive beetle here in Metro Vancouver, so either you prevent a devastating infestation, or you clean up the mess. Hoping it won’t happen is ineffective management!

The following is taken straight from the City of Richmond “Chafer Beetle” site, a nice concise lawn management guide:

Minimize lawn damage caused by chafer grubs by keeping your turf healthy and thick with proper lawn care practices:

* Increase mowing height to 8-10 cm (3-4 in). Longer grass blades mean a longer root system that is more resilient to the larvae feeding. (Ed. It may also help prevent the female from laying here eggs in your lawn, since apparently she prefers shorter grass blades.)
* Fertilize regularly by top dressing twice a year with compost or by using organic, slow-release fertilizers. Leaving grass clippings on the lawn, rather than bagging and disposing of them (grasscyling), also naturally fertilizes your lawn with nutrients after each mow.
* Water your lawn deeply: 2 to 3 cm (½ to 1 inch) once a week to promote a lush lawn with deep roots that better resist insect damage and drought. Follow the water use restrictions in effect from June 1 to September 30.
* Overseed your lawn annually with a grass seed mix will contribute to maintain a dense, healthy, and weed-free lawn. (EdThis can be done with the “top dressing” of compost.)
* Lime your lawn in fall and spring to counteract the soil’s natural acidity. Acidic soil prevents grass from taking up key nutrients necessary for its optimal growth and health.

If you’ve experienced the damage already, you can, like me, plan a new design that doesn’t include grass turf–or very little of it. If it’s Jan 6 and your turf looks like mine, there’s not much you can do until the weather warms up a bit. For now, you can clean up the mess and cover the bare soil with mulch, and in Feb or early March, if you’re hoping to keep lawn in this area, you can heavily grass-seed the area.

Besides the above maintenance regime, there’s a biological control, Heterorhabditis bacteriophora, or nematodesThese are a microscopic round worm that actually feeds on the the CB eggs before they turn into larvae. So it has only a short window of applicability–the latter half of July, after the eggs have been laid, and before they hatch into grubs. You can get nematodes at any nursery, and they’ll give you instruction on how to use them. They’re not cheap, and depending on your lawn maintenance you may need to repeat every year, so it may be another reason to consider removing your lawn.

Critters

I knew the mess was from racoons

I knew the mess was from racoons–CLICK ON PHOTOS FOR LARGER VIEW.

Pretty much every time I go into the garden I see the holes dug by hungry big cute rodents. They’re turning over all that turf that I carefully dug and up-ended to “self-compost” under the wood chip mulch. And seemingly throwing around the edging bricks. They’re heavy!

But I didn't really thing about the entire family--clearly mum's been teaching them how to dig.

But I didn’t really think about the entire family–clearly mum’s been teaching them how to dig.

But with at least four of them, it does explain how they can make so much mess.

Following the path to the stairs to the deck.

Following the path to the stairs to the deck.

They know their way around the territory.

Tried to scare them away-- but we knew racoons--especially mummy racoons-- aren't really afraid of humans!

Tried to scare them away– but we knew racoons–especially mummy racoons– aren’t really afraid of humans!

Giving me “the glare”–you’d think I’d taught them!

Anyone else having the same problem? Anyone have any suggestions? I don’t want to do them any harm, just protect my labour investment.