Category: biology

Self-tutoring about local trees: the tutor makes another observation about local dawn redwoods.

I wrote a few posts about local dawn redwoods, the most recent here. It will lead interested readers back to earlier ones.

Dawn redwood is deciduous here. The dawn redwoods I earlier described are losing, or else have lost, much of their foliage. Their cones remain, hanging rather like acorns, but light-green and about half the size. Their flesh has a twisted look. Without the needles, the cones are quite noticeable.

The source link below has a great picture of dawn redwood cones.

Source:

www.treeworcester.org

Self-tutoring about dawn redwoods: the tutor shares some ideas about identifying them.

In my past two posts, here and here, I discuss dawn redwoods, their particular story, and their presence nearby.

When studying one, you notice its needles don’t appear stiff, but rather soft. They appear in two opposite rows, giving a flat appearance. Furthermore, the branches occur opposite each other. Not only the rows of needles, but the individual needles themselves, grow in opposite pairs. The cones I observed are green, small, round, and plated, similar to alligator skin. Dawn redwoods are deciduous conifers, and one of the two I’ve observed is turning reddish-brown.

The dawn redwoods I’m talking about stand at the west side of a local school yard. As I recall, their trunks are not in the school yard, but just outside it. However, the branches reach over the fence. The trees are both large – between 50 and 100 feet tall.

www.treeworcester.org

youtube: Info Man

www.canr.msu.edu

Self-tutoring about botany: the tutor shares an exciting find from the field.

In yesterday’s post I mention a long connection I have with dawn redwoods, despite only recently becoming acquainted. The dawn redwoods themselves have a story.

Scientists discovered dawn redwoods by fossil before they found living ones: they were thought to be extinct. They used to be plentiful in North America tens of millions of years back. When scientists found a grove in China in the 1940s, it was a revelation. Dawn redwoods were made accessible to visiting scientists who collected seeds.

In nature, the dawn redwood is endangered: it hangs on in a few wild groves in an area less than 250 square miles in China. Ironically, the dawn redwood is easy to grow, and is planted around the world as a popular ornamental! Hence its presence less than a block from where I live, even given its rarity in the wild.

A common name for dawn redwood is metasequoia. In our area, the dawn redwood is a grand, yet demure tree. I will tell its characteristics – and how I identified it – in a coming post:)

Source:

www.botanic.cam.ac.uk

ufi.ca.uky.edu

www.arborday.org

Self-tutoring about botany: the tutor identifies a plant he saw.

Yesterday, in a sidewalk garden, I noticed a striking plant. It had big purple flowers, perhaps 8 to 10cm across, consisting of many long filaments. The flowers reminded me of Canada thistle.

The flowers sat inside bunches of thick, succulent leaves on high stalks, perhaps around 60-100cm tall. The lower leaves, not associated with flowers, were palmate, with long, thin lobes off which more branched.

That’s how I remember the plant, but I only beheld it for about 30 seconds. At home I searched it, from memory, on the internet. I have no doubt it’s an artichoke, perhaps Cynara scolymus.

I didn’t take a picture, but some of the sources below have some.

Source:

lavenderhedge.co.uk

pfaf.org

www.avogel.com

planthardiness.ars.usda.gov

Self-tutoring about trees: the tutor mentions a linden he’s noticed.

In the northwest corner of a local sports field is a hardwood tree, perhaps 70 ft tall. Its trunk is oval; its max diameter might be 18 inches. The bark is gray.

The leaves are heart-shaped, around 5 inches long and wide. Round nutlike green fruits hang underneath, each bunch accompanied by a single oval leaf, completely unlike the tree’s typical leaves.

The tree, from my sources, is either an American basswood or a European linden. Based on leaf size, I suspect it’s the American basswood, which is also of the linden family.

Neither of those trees is native here.

When I was a kid, we had a new linden tree planted in our front yard on the base. I’ve always wondered when I’d encounter another:)

Source:

forestry.ohiodnr.gov

Brockman, Frank C. et al. Trees of North America. New York: Golden Press, 1968.

Little, Elbert L. and Susan Rayfield and Olivia Buehl. The Audobon Society Field Guide to North American Trees. New York: Alfred A. Knopf, 1986.

Self-tutoring about botany: the tutor shares an observation about a red elder.

I know of few trees that produce new blooms while their fruit is on. Yet, I (and now you, too) can witness a red elder doing so.

In the picture below, see the fruit at top left, the bloom at bottom right, on the same tree.

Source:

Pojar, Jim and Andy MacKinnon. Plants of Coastal British Columbia. Vancouver: BC Ministry of Forests and Lone Pine Publishing, 1994.

Self-tutoring about plant identification: the tutor identifies the daisy-like plant growing in the backyard.

Identifying this one took some time, but I believe it’s feverfew (Tanacetum parthenium). The non-pointed, lobed leaves seem to be decisive, as many plants, apparently, have flowers like daisies.

Apparently feverfew can take hold pretty quickly, though it’s not native here. I’ve not seen it in the yard before, but numerous are present now.

Source:

wikipedia.org

www.seasonalwildflowers.com

Pojar, Jim and Andy MacKinnon. Plants of Coastal British Columbia. Vancouver: BC Ministry of Forests and Lone Pine Publishing, 1994.

Self-tutoring about botany: the tutor wades into the distinctions between the European gooseberry and the American one.

Ribes uva-crispa is the old world gooseberry. Its berries can be an inch (2.5cm) across – its leaves, 6cm. However, its nodal spines typically max at less than a cm.

The gooseberry bush I’ve been observing has berries 1cm across, and leaves about 3cm. However, its nodal spines are easily over a cm long. It’s Ribes hirtellum, the American gooseberry.

Source:

gobotany.newenglandwild.org

gobotany.newenglandwild.org

wikipedia.org