last year i had noticed some interesting little "cones" on a couple of the willows along the river. of course i brought some home more because i thought it so unique & "artsy"!! & planned to add it to an arrangement.
so last month i noticed a few more, & realized it was a mutation of sorts, yet still had no clue!
it is an interesting growth on the terminal bud of this willow variety .... mutation of some sort. We have some wild roses that have a mutation caused by wasps... & so i begin to Wondering if this is similar only seeing this on a few trees in a specific area next to the river on the property. #curious. So found out that this is the result of the
"willow pinecone gall" !!! Good to know!
i did some research on line & this is what i found out:
Willow Pine Cone Gall
This gall in the shape of a pine cone, appears on willow stems & confuses many because of its resemblance to a pine cone. In the summer a small fly called a "gall gnat midge"
(Rabdophaga strobiloides) deposits an egg on the stem.
The new larva secretes a substance on the stem which causes the willow to go into overdrive building a multi-layered chamber composed of hardened material that would have been leaves had stem growth not been arrested.
Inside;all nice & snugly resides the wintering larva, which will metamorphose into a gnat when warm weather comes again.
Info said if you split one of these cones open you will find the small pink larva resting inside, unless some wasp-like parasites have invaded the chamber.( i did not try this yet)
The cone growth is what you will see in the Winter. The gall formation sometimes takes on a winter coat of fine fuzzy hair. By the summer, development of the gall as the plant produces an excess of leaves enveloping the larva.
You can carefully peel open the gall, usually you'll find the larva alive & well inside.Evidently it developed its own version of anti-freeze to survive the winter cold.
These cones don’t hold any tree seeds, however. Instead, they harbor the “seeds” of a gall-midge called Rhabdophaga strobiloides. These are willow pine cone galls.
Like most galls, these began in early spring during the active-growth period for the plant and the egg-laying season for the midge. The adult midge laid an egg on the tip of the twig, right where a single, dunce-cap-like bud scale protected baby leaves. The larva will hatch in early May & start burrowing into the willow stem. Some combination of the chewing action & saliva of the newly hatched larva triggered an increase in plant growth hormones. Cells grew bigger & more plentiful, but the stem did not extend. Instead, leaves once destined to flutter along a twig now layered together in the cone-like structures, this is what caught my eye.
What’s fascinating is just how much the larva can control the plant. One study found that the twigs hosting a gall were larger in diameter than twigs with no gall—even if the twig did not have leaves. Bigger stems were correlated with bigger galls, and bigger galls were correlated with bigger larvae. This confirms the hypothesis that the larva somehow draws in the products of photosynthesis from other (probably un-galled) twigs in order to spur the growth of the gall, the hosting twig, and the larva itself.
This type of control may seem creepy, but it is frighteningly common in the world of parasites. Parasitic cordyceps fungi force ants to climb a plant and attach there before they die, providing a breezy platform for dispersal of the fungal spores.
so now we know!!