A few recent encounters - and an answer to ragweed

24 August

Today, I offer a few encounters during a week that, despite being a little too hot and dry at times, is already showing signs of approaching autumn - especially in the quality of the light in the early mornings. I also have something helpful for people who suffer from ragweed allergy, but you have to read the rest of the post to get down to where it lies at the end 😉

A (New) Butterfly

To be precise, a new butterfly for the garden but not a lepidopteran lifer. Quite small, maybe 3cm across, and flitting around a patch of Rudbeckia flowers alongside one of those small blues that never settle to be examined. I only had my iPhone for a picture, so apologies for the low detail, but you do what you can. This is one of the Checkerspots, specifically a Northern Crescent (Phyciodes cocyta) … to the south they are more a July species and normally only around in mid-August near the northern limit of their range.

A butterfly of the family Nymphalidae with distinctive checkerboard patterns on the wings, in black, orange, and white. They are primarily found in North America and are often associated with specific host plants for their larvae, making them sensitive to habitat changes … the Northern Crescent needs Asters for their larvae - plants that are plentiful hereabouts.

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Patio Weed-control Service - new recruit in training

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Meadow-rue

Meadow-rue is the common name for plants in the genus Thalictrum of which there are some 120-200 species. They are perennial flowering plants in the buttercup family, Ranunculaceae, native mostly to temperate regions. This particular species is well over six feet tall and seems to appeal to late summer bumble bees though most pollination is by wind. Other species may only achieve a few inches in height. The flowers have no petals, what you see in this photo are purple sepals. This specimen is not a native to North America, although several species are - in fact I think it likely that this is Lavender mist meadow rue (T. rochebrunianum) which is from Japan - so not native but we like it and if the bees do too, then all is well.

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Common Grackle

A bird that it seems most people have a down on but which I rather like. That beady eye and shiny head are marks of character.

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Hopefully, something interesting … I’ll tell you all about it next weekend. This is not unassociated with the next item …

Preaching to the converted here. The places around our homes are teeming with thousands of different species, including wildflowers, trees, fungi, insects, mammals, and birds. Simply noticing and naming these species, and keeping lists of them, fosters an appreciation for nature and the intricate relationships that sustain ecosystems. Altered weather patterns, rising temperatures, and shifting seasons disrupt these natural rhythms. For instance, early flowering plants impact insects that depend on them for food, which then affects birds that rely on insects for their young. Going for a walk can reveal the challenges species face firsthand. This strengthens our sense of responsibility for fellow lifeforms and encourages conservation efforts. Protecting our world is urgent.

At the same time it’s also great fun to keep and share lists of the what, when and where so we can document the changes. Our notes and observations can be made available to the scientists working to ensure the future survival of far more than my notional 1001 Species.

Mind you, keeping lists also means this …

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Now - Ragweed Season

There is at least a partial solution to this seasonal allergen-producing plant - just stop mowing it. Counter-intuitive, I know. Read on for an explanation.

Eradicating ragweed without using herbicides (which I do NOT, ever, advocate) is mostly a losing battle. If you can get the roots out then you have won with that specific plant, but for the most part ragweed is broken off or cut during mowing and that’s when the plant shows you it knows best and the roots are left. The early shoots grow tall and make it visible ... but it also makes it easy to be seen by grazing animals. The plant has evolved an answer to being eaten (or mown these days) and that is that secondary growth does not grow tall but spreads low, often horizontally along the ground where, the flowers being green, it is much harder to see. Survival of the species. The other thing to note is that even if a town and its residents are 100% efficient at getting the plant out by the roots on public land it is still in gardens and in out of the way corners. BUT ... mowing actually makes things WORSE.

(Quote): In general, grasses are superior competitors to ragweed. Tall grasses are capable of shading the shorter ragweed plants, which affects their ability to collect energy for growth. Ragweed is largely inconspicuous because it has taken on a spindly growth form. When grasses are grazed or otherwise reduced and more light is made available to the ragweed, the result is a ragweed plant with more branching and leaf production. Studies show that ragweed may be 30 percent taller in ungrazed patches, but 50 percent heavier in grazed and mown areas.

In other words, the practical answer to ragweed is NOT TO MOW it, but to let the grasses grow long and outcompete it. Bonus - you get more colourful wild flowers too.

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Stop-press

I happened on this just ten minutes before publication this morning:

Quote:
Scientists work on problems most people don't know exist. They spend decades perfecting yeast that keeps bees healthy, mapping where trees have the most impact, and figuring out why birds sing longer under streetlights. Their work doesn't generate outrage on social media or cable news debates, but it shapes the world our children will inherit.

Progress occurs through the patient work of people who believe their small contributions make a difference. While we argue about everything else, they continue to measure, test, and refine our understanding of how the world works.