Zombie mold

Some zombies are real - if one includes black sooty mold in the class of zombies. They are nearly impossible to eradicate, and they will always bounce back from a beating.

Like Sisyphus and his stone the most frequent activities seem to be repetitive, trying to keep the existing plants in good condition. Never mind expanding the garden with new plants or hardscape features, just staying at "zero" takes a lot of effort. As a volunteer, my work allows the greenhouse staff more time for higher-level tasks.

Moldy windows and sills

Today my assignment at the U of M Conservatory greenhouse was to clean sooty mold off from window glass, and to clean debris that has collected on window sills. I've written about this topic before, and I reiterate the subject to highlight the constant attention to detail needed to keep the environment clean for the plants to continue to thrive in a confined space.

The picture isn't pretty, but I show it again on my blog to emphasize the ever present pressure of parasite insects which suck the sap from leaves resulting in the formation of sticky "honeydew" poop. The honeydew is rich with nutrients which attracts mold to grow and cover the leaves. The honeydew also rains down on any hardscape surface under the plant.

Sooty mold is a waste-basket term for a number of fungal species. The black color is produced by pigments within the fungal organisms. The fungi do not harm the leaf directly, but the pigment reduces photosynthesis in the leaves, ultimately damaging the health the plant.

Sooty mold on a leaf, with brown scale insects being eaten by a white predator larva which were introduced to help reduce the production of honeydew

Clean glass panes and window sills, after I scrubbed off sooty mold stains

Sooty mold is just one of many reasons to keep surfaces clean. As the air circulates in the greenhouse, it deposits dust containing the eggs of insect pests, as well as viral and fungal pathogens. It is far easier to keep the plants healthy if the "pest pressure" is reduced.

How could I not stop and stare?

As I worked to clean surfaces, there were a few show stoppers today:

Masdevallia veitchiana, orchid of Peru, near Machu Picchu

Since the orchids are still in bloom, here is another fine creature:

Coelogyne nitida, orchis from Nepal and China

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