Sawfly - Birch Wood Wasp (Xiphydria mellipes)

We have discovered a refugee family trying to keep warm in our house. We're hoping that a certain blogger can help us at least generally identify the critter.

I am at a loss to even venture a guess, I'm not even sure if I can assure our concerned daughter that it doesn't bite. We have found 3 or 4 over the past few weeks, usually alone and somewhat docile but moving. Usually crawling slowly across the floor, the last guy attempted to fly but could not quite leave the ground (see action shot below).

Length estimated at 15 mm. Using only a 5-year-old point-and-shoot camera (I guess that's old in electronic years), I must say I'm surprised some of them sort of turned out.

UPDATE: This bug has been identified as a Wood Wasp (a type of Sawfly) by 'The Home Bug Gardener' and species confirmed by Robin Leech via Albertabugs via Henri Goulet: "This is a Xiphydriidae. The species is Xiphydria mellipes associated only with small (less than 3 inch) branches of dead birch." Thanks to everyone for their help!

The bug's home is clearly small diameter paper birch branches we cut last year and placed inside for use as coat/hat racks. The wood wasps are waking up confused and disoriented in their new interior habitat! I have confirmed online that wood wasps do not sting and do not pose a threat to structural wood in the house (I guess that assumes small diameter birch is not used for home construction in this case!).

I think this helps with our decision to keep at least some of our dying paper birch as a bug and bird sanctuary (I was debating chopping them down). I wonder who else is living in there??

Alberta Local Grown Potatoes (Conventional)

Recently talking with some friends about how potatoes are grown commercially in Alberta, I realized I know very little about how the potatoes we buy in the store are grown. We try to buy local food when we can but often don't know much more about local food than imported. I don't really know much about growing them in our back-yard either, but I'll save that for another post!

Reading up on the Alberta Potato Growers website has provided some interesting info about locally grown Alberta potatoes, some of which I'll summarize below:

• Potato farming in Alberta expanded from 26,600 acres in 1995 to 51,000 acres in 2008
• Compare with 300 acres in 1917 and 600 acres in the 1930's
• 9.3% of potatoes grown in Canada are grown in Alberta (by weight)
• 1.5% of potatoes grown globally are grown in Canada (by weight)
• See instructions about how to grow your own potatoes in Alberta
• Alberta potatoes are grown commercially for three different general markets:

Table Potatoes

• What we buy at the grocery store
• Only 5% (3.7 sq mi) of Alberta potato acreage in 2008
• see historical downward trend, acreage amounts exclude market gardens with less than 5 acres, and of course, my back yard

Process Potatoes

• Potatoes used to make processed foods such as french fries and potato chips
• 79% of Alberta potato acreage in 2008
• Acreage in Alberta devoted to this potato market more than tripled between 1997 and 2002!
• Table and Process Potatoes are typically grown more in southern Alberta (irrigated) and seed potatoes more in central Alberta (not generally irrigated)

Seed Potatoes

• Potatoes grown and bred to sell as seed to other growers
• 16% of Alberta potato acreage in 2008
• 75% (more than any other province) are exported, mostly to the United States and Mexico
• Certified seed potatoes from Alberta are in high demand because of the colder climate, which results in fewer disease and pest problems
• More than 100 varieties are grown in Alberta
• Most are grown in central Alberta without irrigation because natural rainfall is more plentiful than south Alberta
• A few growers near Edmonton occasionally apply supplemental irrigation from nearby rivers and streams
• Thorough inspections enforce zero tolerance of bacteria and viruses
• Seed Potato Farm Contact List - Buy seed potatoes directly from local farmers!
• Top 10 varieties sold from Alberta are:
• Russet Burbank
• Russet Norkotah
• Ranger Russet
• Shepody
• Atlantic
• Umatilla Russet
• Norland
• Yukon Gold
• Private Varieties
• Other varieties

We are hoping to find local sources of organic potatoes to buy in winter when our garden supply runs out. I've come across at least one grower (Gold Forest Grains Farm) near Edmonton, and we hope to find some near Calgary.

Why Buy Organic Potatoes?

Unfortunately, conventional commercial potatoes receive more chemical application than most agricultural plants. Typical chemical application schedules used to grow potatoes in Alberta includes:

• Fungicide applied to seed potatoes before planting (decay prevention in damp soil)
• Pesticides sprayed during growth (weed control)
• Fungicide sprayed every 7 to 14 days throughout summer (Late Blight fungus prevention)
• Late Blight was what caused the infamous Irish Potato Famine
• Conditions are generally too dry in Alberta for Late Blight to occur, but fungicides are applied anyways as a precaution
• Chemical fertilizer, mostly Nitrogen, is applied (via irrigation in southern Alberta) from mid-May through the summer
• Leaf tests are performed to ensure the appropriate amount of fertilizer is applied
• Herbicide (desiccation) and/or mechanical operation (vine killing) is applied to kill the potato at the end of the growing season (August to October, depending on the variety)
• Dessication/Vine Killing improves skin-set (toughens skin, good for shipping), bruise resistance, storage life, appearance and vine-tuber separation [note that vine killing is accomplished in the home garden by simply removing the potato vines 2 to 3 weeks prior to harvest]
• Potato vine dessicant herbicide options include the following chemicals:
• Carfentrazone
• Diquat
• Endothal
• Glufosinate
• Pelargonic (or Nonanoic) Acid
• Pyraflufen
• During storage potatoes receive a hormone (typically Chlorpropham aka CIPC) via the ventilation system that inhibits sprouting*
• Potatoes can typically be stored up to one year

*An interesting note: A study found peeling potatoes removed 91−98% of total CIPC residue; washing reduced residues by 33−47% [Source]. There are organic sprout suppressants/inhibitors found be be effective, such as the essential oil of various herbs and hydrogen peroxide (approved as an organic sprout suppressant).

I understand that growing organic potatoes on an industrial or small scale would be more difficult, thus the higher cost of organic foods. But I wonder more and more if the organic option might more closely reflect the "real" cost of growing food in a "normal", healthy way? It is sad that the organic farming industry seems supressed (economically, politically, etc) in North America in many ways, or at least this is the perception I have. But this seems to be a trend that is already changing as we speak. The buying public is demanding it.

For now, I will continue to grow mostly organic potatoes in our backyard and buy high quality locally grown Alberta potatoes, but will be on the watch for organic options beyond our backyard. I mentioned "mostly" organic potatoes in our backyard as I have not been using organic seed potatoes, I have yet to source some organic suppliers for this.

Common Purslane (Portulaca oleracea)

I'm finally getting around to studying some of the typical weeds I find myself pulling regularly in the garden. I suspect many of them are edible and hope to try eating some, since I'm pulling them anyway! Now is the time to learn while the plants await next spring. So today I'm learning about:

Common Purslane (Portulaca oleracea), also known as Verdolaga, Pigweed, Little Hogweed or Pusley.

Photo by José Luis Gálvez

Summarized from the Wikipedia article linked above (see article for references) unless otherwise referenced:

Apparently the leaves, stems and flower buds (the latter of which I've never seen) are edible and in fact eaten regularly in Europe, Asia and Mexico. There are 40 varieties cultivated. The plant has adapted to grow extensively from North Africa, through south Asia to Australia during past centuries. There is some evidence of this species in North America in the pre-Columbian era. The little yellow flowers appear only if rainfall conditions are optimum and only for a few hours on sunny mornings. Likely why I've never seen them. Like most weeds, the plant grows well in poor quality, drought-prone soils.

Purslane is a succulent herb reported to have a peppery, slightly sour and/or salty taste and can be eaten similar to spinach (fresh in salads, stir-fried or cooked). It is considered to have similar taste to spinach and similar texture to okra [>]. It is also good in soups due to its mucilaginous quality. At one time Australian Aborigines used the seeds to make seedcakes. It is best harvested in morning or evening [>].

Purslane contains more Omega-3 fatty acids (alpha-linolenic acid in particular) than any other leafy vegetable plant. It contains an extraordinary amount of EPA (Eicosapentaenoic acid) for land based vegetable sources. EPA is an Omega-3 fatty acid normally found mostly in fish, some algae and flax seeds. But note that fish oil typically contains 750 mg/tsp of EPA (source: bottle in our fridge) compared with 0.01 mg/g in Purslane. Doing the math, you need to eat 75 kg of Purslane to get the equivalent EPA from 1 tsp of fish oil. Purslane also contains vitamins (mainly vitamins A, C, some B and carotenoids), as well as dietary minerals, such as magnesium, calcium, potassium and iron. It also contains potent antioxidants.

Hmm, maybe I can cut back on my vegetable plantings and encourage growth of Purslane instead!