Cleaning a conifer, with leaves rather than needles

Again I was able to cycle to the GH. The weather was a bit steamy with high humidity. There were broken clouds threatening to coalesce into thunderheads at some point - they didn’t. The sky on the return trip was sunny and hot.

My first task was to help B wash dirt plastic and terracotta pots that had been emptied. The plastic pots were going to be dipped and rinsed in an antiseptic solution of some sort - located in the pot cleaning room. The terracotta pots were to be sterilized by heat after we had rinsed out the dirt chunks. B had set up the hose outside in the courtyard next to the workroom. The pots she had selected took about 45 minutes to clean. She brought the pots to the cleaning room to finish the process. The pots will be reused, cleaning them helps to prevent the spread of pathogenic organisms: bacteria, fungi, and viruses.

The next chore was helping Curator J and B clean the sooty mold and scale from a couple of podocarp (family) trees in the gymnosperm clade. They were both grown from seeds collected in North Vietnam, and eventually donated to the GH. Curator J is not a fan of this sort of plant scavenging - he would rather the plants were obtained through reputable processes. Anyhow, these two plants have strap-like almond-shaped leaves rather than needles (like other gymnosperms). Nagleia nagi is the scientific name of the plant, also called Asian bayberry for its fragrant seed berries. The plant is dioecious, males and females, which spread pollen by air. The habit of the tree branches does, however, resemble a small conifer tree.

The plants were covered with black sooty mold from a heavy infestation of scale, dozens of parasites covering each leaf. Curator J and I tackled the cleaning of the larger (6-foot bush), B cleaned the smaller 3-foot plant. Fortunately, the leaves are quite thick and strong, they were easily cleaned without being damaged in the process.

Conifer: Nagleia nagi (Asian bayberry)

The final task was to complete the cleaning of a small bonsai-like cactus plant: Leuenbergeria portulacifolium. It too was covered with scale insects and black sooty mold. The challenge was to clean away the soot and scale from delicate leaves set between spine needles (arising from areoles). I found the best combination of tools was a toothbrush and a small jug of isopropyl alcohol (70%). Initially I thought it was a euphorbia because of the presence of leaves and spines. But the needles arise from areoles, which is a feature of cacti, not euphorbias.

Cactus: Levenbergeria portulacifolium (pink rose cactus - not a euphorbia)

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