/headhouse

aborists are in charge of making sure that trees are kept healthy and in safe condition for people in the area. they spend a lot of time pruning, watering, fertilizing, and treating trees for parasites. it was kind of astounding to see what a well-pruned tree looked like. they ended up so much tidier than the trees i see when i walk around my city. regular pruning is important because in the wild, trees tend to just discard dead branches by dropping them, but in a campus like a zoo that becomes a hazard.

pruning has to be done correctly, so as to send the tree signals that it no longer needs to try to support the missing limb and so that the wound will close without getting infected. this also depends on the season and whether they're flowering or not; doing so when they are flowering can also introduce them to infection.

there are a lot of different kinds of parasites & infections trees can get, from bugs or fungus or just being planted wrong. scale is pervasive and annoying, especially because there isn't an easy way to get rid of them once they mature. more on scale management in the greenhouse section. one thing that they do is spray the trees down with mineral oil to kill them when they're young.

watering is important, especially in arid areas where trees aren't really meant to be growing. they need more water than the landscape can account for. deep root watering should be done in a grid pattern farther from the trunk than you would expect. the roots travel far!

browse is really cool, one of my favorite intersections of horticulture and animal keeping. some of the species of bushes/trees/etc that grow on zoo property can be used to feed animals or provide enrichment to enclosures. things like honeysuckle, hibiscus, lobster claw, and some trees i don't feel confident enough in listing. it's really crucial that whoever is in charge of browse can accurately ID lookalike species so that nonedible plants don't sneak into meals.

browse is pretty grueling as a job because it involves collecting, cutting/organizing, and dropping off bundles to the animals. it's three jobs in one! it's also pretty funny to hear about the animals that are picky, and who likes certain plants. i think it's so cute.

browse and arbor often go hand in hand since some of the tree prunings can be browsed out and it's convenient if that tree is going to get pruned anyway.

mostly for outdoor gardens, maintenance is pretty much what it says on the tin. this is essentially doing a lot of watering, weeding, and designing to keep public-facing gardens looking nice. i'm sure there's a lot more too it than that, but i was mostly only exposed to the basic tenents.

production is concerned with, well, producing plants to be used around the campus. these can be grown from seed or ordered from nurseries as young plants. there are also large seasonal specimens that are rotated in and out of the houses, or that are kept until new exhibits are ready! ornamental annuals are often grown from seed and then transplanted over the course of several months & deadheaded to ensure maximum bloom when they are ready to be put on display.

the large specimens are kept on a watering schedule based on how long it takes for their soil to become dry. most of them get soaked on a M/W/F schedule. it's fun! you can tell when they are happy with their watering schedule.

greenhouses are incredibly controlled environments and once you figure out the right balance of humidity, light, and airflow, it really just becomes about maintaining it.

biological pest control*

*this is a subset of IPM (integrated pest management), but the full scope of IPM isn't something i'm very familiar with + i'm fond of the pest-predators so i'm just going to talk about them :-)

because greenhouses are controlled growing environments, the plants inside are more likely to suffer from pest infestations since their natural predators aren't present. one of the ways this is combatted is by introducing their natural predators artifically, to keep pest populations in better check. the most common pests are soft shelled scales, mealybugs, and aphids.

figure 1	our beautiful friend the mealybug destroyer (cryptolaemus montrouzieri)
figure 2	diagram of how parasitic wasps control scale populations