Different species have different tolerances for stresses like drought, and this one might not be as adaptable or might not have established well enough to withstand minimal rain and high heat this summer. This year's conditions became so stressful for plants (in several areas of the state, at least, many of which are still under drought) that even well-established, drought-tolerant species were succumbing to damage or death.

Was the goldenrod being monitored for watering needs and periodically irrigated? In the photo, it looks quite dry (both the plant and the exposed soil around it, including nearby plants), and if the soil is somewhat dry to the touch a few inches deep as well, a good two-gallon (approximately) soaking for this plant would probably help. Browned leaves or dying stems cannot recover, but watering should help to support the roots. Stems that have fully browned can be cut back. We don't see indications of a pest or disease, though sometimes stem-boring insects or fungi that infect plants at the crown (where stems joint the roots) can cause wilting and dieback. Typically, though, that type of dieback looks different than this, which is one reason why we suspect insufficient root moisture instead.

Miri

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