'Tis a Gift to be Simple

I can't begin to imagine the number of times I've encountered a complicated problem and then search for a complicated solution, while a simple solution would have been just as good. Today at the University of Minnesota Conservatory, where I volunteer, the greenhouse staff are continuing their push to treat and restore plants which have become threatened by pests. I was assigned the task of using a sharp spray of water from a hose to knock pests off from the leaves of plants. It is a simple physical means of control. No chemical poisons, repellents, or expensive predators are involved.

While I walked around the greenhouse looking for infested plants to douse, I spotted this blooming gem. It has the genus name Hippeastrum, and is in the same family as the common amaryllis plant.

Hippeastrum, in the same family, Amaryllidaceae, as the common amaryllis plant

A sharp spray of water was used to knock of scale and mealybug insects from the leaves of two dozen plants.

While on the topic of plant pests, today the greenhouse staff identified a pest that I'd only heard about, but never seen in person: the ground mealybug. This dastardly creature exists under ground where it feeds on plant roots, slowly robbing them of their ability to support the plant. The first indication the problem exists is when the plant is essentially dead. The staff were surprised to discover a heavy infestation of parasite insects on and below the surface of the soil.

Discussions are underway about the best way to manage the plant, but it probably will not survive. All of the plants around the infestation must be carefully inspected for further spread of the ground mealybugs (Rhizoecus). This problem will not be solved by a simple spray of water from a hose. Rather, the roots will have to be cleaned and treated with either a biologic control (predator like nematodes), or using a systemic insecticide. Chemical treatments are the method of last resort.

Dying Fuchsia plant

Tiny white spots on the green moss are mealybug parasites which have been feeding on the plant roots.

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