Pests

I have an aphid infestation. So far, it is not too bad in the sense that they have not taken over EVERY plant, but they seem to be targeting the black mangroves and the rare tea mangrove. NOT GOOD. Plant-eating aphids = my enemies, particularly when they are my research plants. Gardeners have tricks like spraying them with a hose (didn't work) and spraying them with soapy water or even pesticides, but I don't want to apply that stuff and inadvertently mess with my seedlings' growth. Enter the biological control: ladybugs. Garden stores sell ladybugs as a natural pest control. There are a bunch of different species of ladybugs (which are really beetles, for you non-entomologists out there), and some eat aphids and some eat leaves and some eat mildew or bacteria, so I am just assuming that the garden store sells the kind that eat aphids. However, it turns out that garden stores around here don't sell aphids. It is actually easier for me to order them online from Home Depot and have them shipped, because the closest ladybug store is an hour's drive away. So in a few days, I will release ladybugs onto my plants and hope they get the job done. In the meantime, I will be crushing aphids with my fingers, unless a hurricane gets to them first.

Scientific Discovery

It's time to talk science. I am studying the rare tea mangrove (Pelliciera rhizophorae), and trying to understand what makes it rare. Very little is known about the ecology of this plant, so there are a lot of unanswered questions. Leaves of the tea mangrove have little glands on them, and no one knows what they do. Possible uses for the glands are: salt secretion--some of the other mangrove species secrete salt out of specialized glands, allowing them to live in salty environments that most plants can't tolerate; extrafloral nectaries--I'll get back to this; mite domatia—little holes that mites can live in, and in return clean the leaf surface of fungi and parasites; or nothing--random glands on leaves seem to be characteristic of tropical plants so maybe they don't do anything special. See the photo below; look at the white stuff on the leaf.

I think the glands are extrafloral nectaries. The plants are not secreting salt and don’t live in super salty environments anyway. I have looked for mites on many leaves and they aren’t there. Plus, the holes aren’t really big enough, even for mites. When I look at leaves out in the field nothing seems to be coming out of these glands. However, I am currently growing one specimen as a houseplant, and I was surprised to see white goo coming out of the leaf glands! Hooray! They ARE doing something. But what? I started collecting the white stuff, which actually hardens into a little ball, but it will take awhile before I have enough of it to chemically analyze and figure out what it is made of.

The point of extrafloral nectaries is usually to recruit an animal (such as ants) to take part in a mutualism. The plant provides a nutritious substance such as sugar or protein or lipids, and in turn the ants protect the plant, attacking any other herbivores that approach. A classic example of this is the Bullhorn Acacia, which recruits ants with protein-lipid goodies called Beltian bodies, and the ants take care of any threats to the plant, including herbivores and other plants growing near the Acacia! I often see ants on individual trees of the tea mangrove, and ants are even present on the plants I am growing at the lab in Florida. The reason I am convinced that the glands are extrafloral nectaries is that one day I saw an ant crawl around the plant and stuck its head into each gland on each leaf, like it was looking for something to eat! I have seen other obnoxious herbivores hanging out around the leaf glands, and my hands have also become covered in ants when they provoked a leaf for too long.

I probably don’t see the white goo on leaves in the field because the secretion gets used/eaten quickly. I was able to capture it on my houseplant because there are no insects inside to gobble it up. I don’t know if there is one or multiple species of ant that are usually associated with the tea mangrove in the wild, so I’ll have to make some ant collections next time I travel. For now, I’ll focus on collecting leaf liquid!

Dubious delicacies

In my last post I mentioned a few of the food items I tried in Florida: fried alligator and fried pickle chips. Today I would like to discuss another two: candy apples and boiled peanuts. I always thought candy apples were a myth. I am familiar with caramel apples, the delicious caramel-coated concoction popular in autumn, at apple orchards, and around Halloween. You can buy them at Disney World and at Whole Foods, which is pretty much Disney World for foodies. So when the books I read as a child (such as The Berenstein Bears’ Go Trick-or-Treating) showed bright red candy apples in their illustrations, I assumed that was an embellishment because red is a much more interesting color than brown.

It turns out I was mistaken. Bright red candy apples DO exist, and I bought one at Fort Pierce’s monthly Friday Fest. It was red, hard, coated in cherry-flavored hardened sugar, and leaked red coloring on anything it touched. It was not possible to bite into the apple because the coating was so hard, and licking it brought to mind the old Tootsie Pop commercial where the owl asks, “How many licks does it take to get to the center of a Tootsie Pop?” Now I am wondering if this is a geographical phenomenon. I have a low sample size, but the person of East Coast origin I asked had seen and consumed candy apples before, but another Midwestern acquaintance had not, and like me, thought they were a myth. So let me ask you, dear readers: have you ever had a candy apple? Where? And why do they still exist?

The second delectable is definitely a southern thing. Boiled peanuts. They came in a Ziploc bag, and it turns out they were boiled in that very bag. They tasted like baked potatoes and had none of the oily, salty crunch I look for in peanuts. But apparently they are very popular here. You can even buy them by the can in the grocery store.

Benefits of working in Florida

Being surrounded by my study organisms, and growing the plants in a climate they can tolerate, is the main appeal of working in Florida. However, this has some not-so-obvious perks:

1. Beach biology. The other day I woke up and saw turtle tracks on the beach from my window. I checked it out and can confirm that a turtle nested there. Will I be patrolling the beach at night with a red-colored light in 55-60 days, watching for little turtle hatchlings? You betcha.

2. Cost of living. I am renting a 2 bedroom beachfront condo for less than I rented a viewless studio in Oakland. And the water is swimmable!

3. Florida food. Local delicacies include fried alligator and fried pickle chips. When in Rome, right? Fried alligator is pretty good, like a less slimy calamari. And fried pickle chips should be on the menu everywhere. Take sliced pickles (like you would find on your hamburger), fry them up like potato chips or french fries, and voila! A delicious, vinegary, vegetable-based appetizer!

4. Endless summer. You may think 90+ degrees is a little too much, but for all you California residents who had nothing in the way of summer this year, a couple months of heat doesn't sound so bad, does it?

Swamp allure

Why would anyone in their right mind want to spend time in a hot, humid, muddy, bug-infested swamp? This is a question many of my friends and admirers have asked. If you have spent time in mangroves, salt marshes, bogs or other swamp-like environments, it is possible you love them but more likely that you hope to never go back. However, you will be missing out if you never go back.
Allow me to explain.

Mangrove forests are unlike other tropical forests in that they are depauperate of plant diversity. In the Americas, a typical mangrove forest has one to three tree species and a smattering of other types of plants such as vines and epiphytes (plants that live on top of other plants, such as bromeliads that grow on tree trunks). Because there are only a few woody species, there tends to be little or no understory. This means you can walk into a mangrove forest and feel like you are in a cathedral, with the branches of trees reaching high above you and nothing obscuring the view for what feels like miles. This makes it difficult to find a suitable ladies' room sometimes,

If the cathedral view is not enough, these forests are full of wildlife that you would rarely see other places. Because you can see farther than in other types of forest, it is easier to see and hear birds, plus if coatis are running through the forest far away from you there is a better chance of seeing them. Parrots squawk high overhead, announcing themselves as they fly by. Toucans rest in tree branches. Hummingbirds and mangrove warblers flash their bright colors in surrounding trees, but you won't see the snakes until they're close. A couple very cool tree frogs (e.g. hourglass; see previous post) hang out on trunks or leaves.

Then there is the adventure aspect. You never know when you might sink into the mud up to your waist, so stuck that you have to take your boots off to get out. You may come across a nest of africanized honey bees and have to sneak away quickly and quietly. There might be a thunderstorm with lightning crashing above and rain pelting down. Or on a calmer day, there is always the creaking sound of dead trees swaying in the breeze, just waiting to fall down.
If you can ignore the heat, protect yourself against the bugs, and don't mind getting muddy, mangroves are very rewarding places to explore.