Monarch Caterpillar Reappears

Saturday, Aug 3, 2019| Tags: Monarchs, weeds, bed bugs

Monarch Caterpillar Reappears on a Weed Historically Deemed Noxious

Out of seemingly nowhere, we discovered a large Monarch caterpillar, in its first year, feeding on a milkweed plant. Monarch butterflies are known to migrate thousands of kilometres. How this large butterfly flops - looks more like flopping than flapping - its wings to travel great distances seems like a good question for the field of aerodynamics.

Another mystery may be their apparent mobility as caterpillars. Tracking them from one day to the next is very difficult. They tend to reappear after you have given up looking for them.

A closer look at their stubby legs, as adorable as their wings are beautiful once they complete metamorphosis, will make you wonder how it gets around so well. Their feet look like suckers, and they just look endearingly fat.

The contradictions don’t end there because it isn’t as though they are well camouflaged. They are rather large, and sport high contrast black-and-white lines with some yellow. When they chew on the milkweed, their long black antennas flail about as though advertising its location for all to see.

Monarch caterpillars feed on milkweed, which was previously classified as a noxious weed in Ontario. Break off a leaf or a stem, white liquid oozes out. Generally, white sap is a sign that the plant is poisonous. Judging from all the pollinators and insects that the milkweed attracts, many beneficial, you wouldn’t know that it is toxic.

Although they pollinate a variety of plants, Monarchs rely on milkweed for reproduction - hence the reason why milkweed was removed from the list of noxious weeds in the Weed Control Act here in Ontario.

Noxious Weeds of Ontario

  • Barberry, common berberis vulgaris L.
  • Bedstraw, smooth Galium mollugo L.
  • Buckthorn, European Rhamnus cathartica L.
  • Chervil, wild Anthriscus sylvestris (L.) Hoffmann
  • Coltsfoot Tussilago farfara L.
  • Crupina, common Tussilago farfara L.
  • Cupgrass, woolly Eriochloa villosa (Thunb.) Kunth
  • Dodder spp. Cuscuta spp.
  • Dog-strangling vine Vincetoxicum rossicum (Kleopow) Barbar.
  • Dog-strangling vine, black Vincetoxicum nigrum (L.) Moench
  • Goatgrass, jointed Aegilops cylindrica Host
  • Hogweed, giant Heracleum mantegazzianum Sommier & Levier
  • Knapweed spp. Centaurea spp.
  • Kudzu Pueraria montana (Lour.) Merr.
  • Parsnip, wild Pastinaca sativa L.
  • Poison-hemlock Conium maculatum L.
  • Ragweed spp. Ambrosia spp.
  • Ragwort, tansy Senecio jacobaea L.
  • Sow-thistle spp. Sonchus spp.
  • Spurge, cypress Euphorbia cyparissias L.
  • Spurge, leafy Euphorbia esula L.
  • Thistle, bull Cirsium vulgare (Savi) Tenore
  • Thistle, Canada Cirsium arvense (L.) Scopoli
  • Tussock, serrated Nassella trichotoma Hackel ex Arech.
  • In case you wonder, spp. is abbreviation for species, which means it includes all species within that genus.

    Did you know that female bed bugs tend to leave their feeding area?

    Monarch butterflies might be one of the most mobile insects in the world. However, cimex, commonly known as bed bugs are surprisingly mobile even though they have no wings. Attempts to control them are likely to fail if treatments are exclusively focused on the bedroom as pregnant females may leave the bedroom (CR.Cooper, C.Wang, N.Singh, 2015), effectively replenishing the population. A balanced management approach, with knowledge of the insect’s true physical capabilities, is necessary for success.

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