Posts Tagged 'trees'

Galls

You may know of my fascination with galls, the structures created by plants in response to insects. In the Botanisk Have in Copenhagen and in the Alnapsparken at Sveriges Lantbruksuniversitet, the Swedish agricultural college, I found these lovely knopper oak galls. They were growing on acorns of Quercus robur, the great oak of Europe, which we usually call the English Oak (cf. hearts thereof), but when in Rome, or more specifically Sweden, it’s skogsek. It is, of course, thanks to a Swede, one Carl von Linne — the family name comes from the lime (linden) trees on the family estate — who is better known as Linnaeus, who codified the binomial naming system that is supposed to be universal. So the full binomial for this oak is Quercus robur L., the initial standing for the namer, yup, Linnaeus. One of L.’s students was the founder of the precursor institutions of the SLU.A gall wasp, Andricus quercuscalicis, causes these oaks to form these when they lay their eggs on the emerging acorns. These wasps need Turkey Oaks (Quercus cerris L.) to complete their life cycle, so finding them in botanical garden settings makes a lot more sense then finding them out in the “wild,” where these other oaks are a lot less common (Q. cerris is native to southeastern Europe and Anatolia/Asia Minor).

Galls like these are full of tannin, a gallic acid which has been used for centuries as a component of iron gall ink. The Magna Carta, Beowulf, and the Lindisfarne gospels were all written in this stuff, which is made from the galls (Oak Apple galls in these cases), iron sulfate, and water.

In Sweden

I particularly wanted to see some sloes, the marble-sized drupes of the blackthorn (Prunus spinosa). My walking stick, which saw me around Dartmoor, is made from the storied wood of this shrubby, hedgy, sometimes-tree. There’s much legend associated with this species; and (black) magic, like, for instance, how they find a long straight piece for a walking stick… Meanwhile, Slån is the Swedish name for this source of sloe gin. The drupes are not very palatable until they’ve been soaked in gin and sugar… but we did see some young Wood Pigeons gobbling them up.I hadn’t realized that hedgehog (Erinaceus europaeus) or Igelkott was on the menu, so to speak, of sights. But our nighttime safari-leader Evan turned one up not two blocks from our lodgings in Skanör. The animal was bigger than expected, about the size of an American football. They bulk up for winter hibernation. After we determined it was not a rock on the lawn, the critter took shelter in a mess of rose and ivy and some kind of diptera aroused by our light. We searched again the next two nights but found no others; this source says they can forage for up to 2 km during the night.

I haven’t yet downloaded my camera camera, as opposed to my phone camera, so pictures of the Kingfisher will have to wait. One was definitely on my list of things to see (we saw two)… But here is a fine consolation prize, worth two in the camera:A Sedge Warbler (Acrocephalus schoenobaenus) after being ringed (or banded, as we would say) by members of the Falsterbo Fågelstation bird observatory. This little songbird is on its way to central/southern Africa, presuming it survives the gauntlet, including the Sahara, along the way.
And then, all things being just, it will return north in the spring.

Great numbers of migrating birds fly over the Falsterbo peninsula, which sticks out like a T from the southwest corner of Sweden, during the fall. It’s the shortest distance over water to Denmark and non-pelagic birds don’t like being over the water too long. The observatory keeps a daily count of passing birds and rings a few in the lighthouse garden and the nearby Flommen reedbeds, where the warbler above was netted, ringed, sexed/aged, weighed/checked for body fat, recorded, and released.

North Woods

We were in Skåne, Sweden’s southern-most county, largely flat and agricultural. But there were certainly pockets of woodlands.And mushrooms.And the fabled Röd flugsvamp (Amanita muscaria), which the Vikings used to get up and go… berserk in the morning.

Franklinia

A late summer bloom. Isn’t the flower rather reminiscent of a camellia? In fact, the Franklin tree (Franklinia alatamaha) is in the same family, Theaceae, as the camellias, along with as its fellow natives Stewartia and Gordonia.. But this North American native is presumed extinct in the wild; it hasn’t been spotted since the early 19th century.This one is in the NYBG’s Native Garden. All known living specimens today are presumed to be ancestors of the seeds collected by Willian Bertram in 1773. He and his father John found them a few years earlier on a not very large tract on the Altamaha River*. It’s still not known why they disappeared in the wild. Was it climate change, over-harvesting by collectors, or the introduction by a pathogen via the cotton production that took over the region?

William Bertram wrote about “This very curious tree”: “we never saw it grow in any other place, nor have I ever seen it growing wild, in all my travels, from Pennsylvania to Point Coupe, on the banks of the Mississippi, which must be allowed a very singular and unaccountable circumstance; at this place there are two or three acres of ground where it grows plentifully.”

*Somewhere in its wending way, the Altamaha lost the extra “a” of Bartram’s day.

Walnuts

Baby, or perhaps teenage, black walnuts. Juglans nigra.And a windfall.

Diospyros virginiana

American Persimmon sex parts brought down during Saturday’s downpour. (I didn’t notice that bumblebee until looking over the photo.)These are the male flowers, rather fleshy bell-shaped things with recurved lobes. And a fruit that’ll never be.

Hackberry

A hackberry drupe. Can we call it a “hack”? It is surprisingly smooth at this stage of unripeness, and extremely difficult to photograph. This is through a 10x loupe.

Other names for the tree include nettletree, sugarberry, and beaverwood, but why hackberry? One source says the Scottish “hagberry,” for a Eurasian bird cherry (Prunus padus), is the source of this name; hackberry is also a name for the cherry.

The genus name Celtis was Pliny’s lotus tree, so that’s no help.

You can rest easy, since my corrections to the Street Tree map have been accepted. You may remember that when I first saw the map I naturally looked up the two trees right below my apartment. They were mapped as Hawthorns. They are now rightfully recorded as Hackberries.


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