Weeding display beds

Today, I primarily weeded the oxalis and mulberry weeds out of the ground beds in Display Room 2 (New Caledonia). The oxalis weeds are virtually everywhere in the greenhouse, from the beds to almost all of the pots. The small leaves easily hide in the tinyest nooks and cracks. I suspect the seeds blow in on the wind. The greenhouse will never be rid of the little devil. I won't even post a photo of the weed for fear it will infest my computer too!

While weeding the beds, I had to be careful not to disturb the small volunteer amborella plants taking root in the bed across from the mature amborella plants. This plant is particularly important since it is native only to New Caledonia in the south Pacific Ocean. The plant is essentially unchanged for the past 250 million years, and was certainly in existance along with the entire history of the dinsouars. It is the perfect specimen to successfully grow in a university greenhouse.

The amborella leaves are thick and waxy, like holly leaves. Small white flowers grow from pedicles along the main stems.

Unfortunately, as with most plants in the greenhouse, the amborella bushes are susceptible to scale insects which extrude fecal sap, which in turn allows sooty mold to cover the leaves and reduce the photosynthetic capacity of the plant. The staff at the greenhouse work hard to mitigate and control the infestations on all of the plants, not only amborella. I've been asked to take a pail of soapy water and scub the amborella leaves on more than one occasion.

It is quite a success to see the delicate small amborella seedlings in a bed across the path from the main bush. The seedlings were eventually relocated to a pot to mature into a larger plant.

Finally on this day in September, I used the nail brush to clean a potted climbing hydrangea bush covered in sooty mold.

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