Tag Archives: water

Golden-backed snipe fly

This golden-backed snipe fly (Chrysopilus thoracicus) landed in one of my bird baths and drifted around for a few minutes on the surface tension. I’m not positive, but I think I’ve seen them do this in past years, too. I wonder whether they are looking for mosquito larvae, or perhaps adults. These flies have predaceous mouthparts, so they clearly hunt something. Sure wish somebody would PCR the gut contents of these things and let me know. Anyone ever seen them take something down?

Colin Purrington Photography: Insects &emdash; Golden-backed snipe fly (Chrysopilus thoracicus)

Here’s another one, albeit one with a damaged eye:

Colin Purrington Photography: Insects &emdash; Golden-backed snipe fly (Chrysopilus thoracicus) with dented eye

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Teaching kids about sugar content of beverages

One out of three kids these days is overweight or obese, and consumption of sugary drinks is a big reason why. Sugary drinks also cause tooth decay (I know, big surprise there), and might even cause kids to be aggressive (or if kids think sugar has that effect, it might have a placebo effect). So I got to wondering what public schools could do … and I think that making a “sugar content” poster in kindergarten is is the way to go. The idea is to construct a display for the hallway or classroom wall that visually shows how much sugar is hidden in common beverages. Here’s an example:

Sugar in drinksThis project would fit in perfectly with most state standards (for example, see page 10 in Health Education Content Standards for California Public Schools). And because it includes numbers (of teaspoons), teachers can use the poster content to visually drive discussions about addition and subtraction. If this poster was done in a fun way, the experience might vaccinate kids against over-consumption of sugary drinks for the remainder of their lives. The parallel to brushing teeth might be appropriate: you teach kids how to do it before school … even though the chemistry of decay is beyond their understanding: if you don’t brush and floss, your breath will be nasty and you’ll lose your teeth. Like many health lessons, that’s best taught to young kids.

There are lots of ways to make the poster, but what I like about the one above is that water (no sugar) and plain milk (contains lactose … which is a sugar) are included. There should also be a sampling of common juices (apple, orange, e.g.) because they are loaded with sugar. And just for scale, it might be good to show how many teaspoons of sugar are in a typical bag of candy (e.g., Skittles).

Poster titles matter here, just like they do at a scientific meeting, in that they can provide a take-home message. “Rethink your drink” is a popular title (it rhymes), but I prefer something that confronts the point more directly. Here are some ideas: “Don’t drink dessert all day”, “Don’t drink your dessert”, or “Sugary drinks are candy drinks”. If snark is allowed in your district, then something like, “Sugary drinks are a sweet way to gain weight and rot teeth!” The idea is to be direct and memorable and to not shy away from the point: sugary drinks can (and do!) make kids fat.

If you want some background information relevant to lesson plans on sugar for K-3 levels, here are some resources from BrainPOP. If you’re looking for more examples of posters, here’s a Pinterest board where I collect them:

Pinterest board Educating kindergartners about sugary drinks on Pinterest.

Posted in Biology, Education, Food, Graphic design, Health, Photography, Science | Tagged , , , , , , , , , , , , , , , , , | 2 Comments

DIY olla planter for swamp milkweed

In my futile quest to attract monarch butterflies to my yard, I recently planted swamp milkweed (Asclepias incarnata).  There are other kinds of milkweed (e.g., the orange-flowered A. tuberosa, butterfly weed) that you can plant here (Zone 7A), but adult monarchs really like the flowers of A. incarnata and the larvae really, really like its leaves.  The problem is the plant likes to be consistently watered, which is hard if you leave the house for a few days in the summer.  So I decided to plant a few plugs into a large pot equipped with a makeshift olla.  Ollas are those beautiful, unglazed terracotta containers used around the world to irrigate crops without much water waste: you bury them next to your plant, fill them with water, and then they slowly release moisture into the surrounding soil.

Anyway, photographs of what’s in my garden are probably TMI, but I wanted to share so that others might be guilted into planting some swamp milkweed, too.  If more people maintained host plants, more monarchs will come … and who wouldn’t want that??

If you’re on board, make yourself an olla with a terracotta pot glued to a saucer.  Or use two pots together — just ensure that you’ve got something watertight. I’m fond of Loctite Premium and Gorilla Glue for getting the components sealed together.  Note that you must use unglazed pots. To facilitate filling of the olla, attach something funnel-like.  For this olla I used a lamp reflector bowl that I found on sale at a hardware store; because I needed a little more height, I attached the funnel on top of a little bit of PVC tubing.

Colin Purrington Photography: gardening &emdash; terracotta-olla-with-glass-funnelNext, equip a planter with a plastic liner so that water will pool a bit at the bottom.  Alternatively, if your planter is wood or plastic and lacks holes at the bottom, just drill a few drainage holes midway up the sides.

Colin Purrington Photography: gardening &emdash; planter-with-plastic-liningHere’s a photograph showing the olla inside the planter.

Colin Purrington Photography: gardening &emdash; olla-with-glass-funnelHere’s a really boring video of water being added to the olla.  But I sped it up so you don’t suffer too long.  But you can skip this and I won’t be offended … I’ve just found that when explaining the olla concept to the uninitiated, they don’t get it unless showed.

Once filled, you can see the porous nature of terracotta almost immediately.  I think this pot is particularly porous (perhaps firing temperature was too low).

Colin Purrington Photography: gardening &emdash; water-seepage-ollaAdd some sort of floating ball to your funnel so that when the water level goes down, the ball acts as a stopper for the olla, preventing evaporation. Other people have caps for their ollas — that works, too.  I’ve never seen balls used before, and they amuse me.  Yes, I’m easily amused.  Also gives me a quick visual for when the funnel level has dropped.

Colin Purrington Photography: gardening &emdash; ping-pong-ball-olla-capAfter you’ve confirmed that olla doesn’t leak from the glued seams, add soil and plants. Of course, if your olla leaks, dry it out and add glue or caulk (the white stuff you see at the bottom).

Colin Purrington Photography: gardening &emdash; swamp-milkweed-in-olla-planterThis shows how the ball (ping pong ball) seals the neck.  Works like a charm.

Colin Purrington Photography: gardening &emdash; ping-pong-ball-olla-cap-sealedNow I’m waiting for the darn monarchs.  I hate this part.

By the way, ollas work well for any plant.  I have about 10 in my garden, all homemade (you can buy fancy ones, but shipping terracotta is expensive).  Really great if you find yourself traveling during the summer, or have plants that don’t tolerate even a single day of neglect.  If you hook them up to rain barrels via a siphon (future post), you can have pots that water themselves entirely.

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