Early goldenrod (Solidago juncea) gets its name from blooming early. In central Massachusetts where I live, their buds are already well formed before other species have even begun to develop their inflorescences.
Inside these buds, pollen and ovules are developing, producing haploid sperm and egg cells for fertilization. The stamens and ovaries are providing diploid cells for support. It’s a productive time.
The growing tissues need a supply of materials, and the phloem provides it by translocating amino acids, sugars, and more to where they can be assembled into new cells. Some photosynthesis takes place in the buds themselves, some occurs in the green parts of the inflorescence, and some occurs in the lower leaves. The green parts of the plant are sources of raw materials for the process of reproduction.
In southern parts of the North America, some goldenrod species bloom year round, but in northern areas, they wait until summer. Everything happens in a small portion of the year, and some things happen so quickly that they are truly fleeting. In this window of opportunity, seeds and their encompassing fruits (achenes) will come to be.
The public part of the process – blooming – is not far off. The stages are being set. It’s going to get exciting. At the cellular level, it already is.
A Life Cycle Tied to Early Goldenrod
You might have heard of jumping plant lice (family Psyllidae) because they pierce plant tissues with needle-like mouthparts and feed on what’s inside. Some of them transmit diseases of plants while they feed, like citrus greening, and are therefore of great economic importance. Others just feed.
At least one species, Craspedolepta veaziei, feeds on goldenrods, especially early goldenrod, Solidago juncea. In June, adults move up the stem of the plant on to the branches of the inflorescence, feeding wherever they sit. And they are mating. And after they mate, the females has to lay eggs.
Inside the flower heads of early goldenrod. By the time the flowers bloom, the adults are nearly all gone (as shown in the graph; Craspedolepta veaziei used to be named Aphalara veaziei). But the eggs are just getting started. They hatch among the flowers inside the flower head where they are hard for enemies to find, and where they can feed as the flowers develop from bud through blooming into fruit.
Goldenrod species that develop later are not good hosts for these psyllids. They need new flower buds when they are ready to lay their eggs. Early goldenrod is the plant that has buds at the right time.
But by the time the flowers have become fruit, the psyllids are still immature. Where do they go? I think they spend the winter in the soil, perhaps associated with the underground parts of goldenrods, or perhaps just waiting, in a dormant state called diapause (it’s an entomological term – there are so many).
The next growing season, large nymphs that have begun to resemble the adults, except for the absence of wings, feed on the stems of early goldenrod. They seem to be well adapted for feeding and developing in conjunction with this host plant. As far as I can tell, the plant is not significantly harmed by the psyllids. Perhaps the late nymphs and adults, being exposed on the surface of the stems, are discovered by enemies often enough to keep these bugs from becoming too destructive.
I apologize for not having a picture of this small insect, but you can get a sense of their appearance from photos posted on the web: https://inaturalist.ca/taxa/207542-Craspedolepta
Owen D. V. Sholes. 1984. Responses of arthropods to the development of goldenrod inflorescences (Solidago: Asteraceae). American Midland Naturalist 112: 1-14. http://www.jstor.org/stable/2425450
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