February 2015 Supermarket Orchid, Mass marketing has hit the orchid world!

The phalaenopsis, or moth orchid, is a favorite gift orchid and is readily available in supermarkets and garden centers. It comes in a variety of colors and exotic patterns, and with care the long-lived blooms can be enjoyed for weeks. Photo by P. McDaniels, courtesy UTIA

Did someone bless you with a beautiful orchid? Mass marketing has hit the orchid world!
Among the most popular orchids for gifting are cattleyas (pronounced “KAT-lee-uh”). Another favorite gift orchid is the genus phalaenopsis (pronounced “fail-en-NOP-sis”).  This orchid is nicknamed the moth orchid because of the shape of its blooms. Both come in a variety of sizes and colors, are readily available in grocery stores and garden centers, and can look just as good in your home as the store.

In spite of the fact that my friends think I can grow anything with little regard for plant rules, I will confess that I managed to kill the first two orchids I was given years ago by simply not consulting the experts. Orchids are epiphytes or air plants that have developed specialized water-storage organs. They like to attach to moist tree bark in a tropical atmosphere. Thus, they have their own set of recommended growing practices. The American Orchid Society (aos.org) gives great advice on keeping your new friend healthy and blooming. 

Both cattleyas and phalaenopsis appreciate a lot of air movement and a long day of filtered, bright light. They don’t appreciate direct sunlight but do thrive in temperatures between 60 and 85 degrees Fahrenheit. Living in an east-facing window usually makes them happiest.

Both orchids should be kept in free-draining growing media. The AOS recommends even moisture, although allowing the media to dry slightly can be beneficial. I recommend you water your orchid once a week, at most. Be sure the water can drain and does not stand in the pot. The pot it came in probably has no drainage, so your job is to not overwater. You can also create drainage holes.

Orchids should be watered in the morning. Because the water should run through the pot, place the plants in the sink. Tepid water is recommended. Also, do not use salt-softened or distilled water. Let the water run through the plant for a minute or so. Be sure to let the plant drain completely. If any water gets trapped in the leaves, use a paper towel to blot. This will help avoid crown rot. If you’ve read that you should just lay some ice cubes around the roots, I have found that generally works, also.

As for fertilizer, there are a number of mixtures and brands, but the AOS recommends that any fertilizer you use should not contain urea. Their website discusses recommended methods. If you want to try a home fertilizer brew, you might try your morning brew. I dump the dregs of my coffee pot into my orchids once a week, all year around.  For an average pot with a 5-inch top measurement, about 1/4 cup of these leavings works best. Doing this will negate the job of occasional fertilizing, as the dregs give your new friend all the encouragement it needs to do its best. I use “high test” (caffeine) coffee leavings, but a friend is using decaf on hers. It will be interesting to see which formula produces the best results. 

When orchids have completed their flowering cycle, it’s time to cut the flower stem to encourage a new bloom on a healthy plant. Again, the AOS has a number of tips about getting your orchid to re-bloom. For phalaenopsis, they recommend cutting the flower stem ½-inch above the first or second node. Be sure your pruners have been disinfected. The plant will most often grow another flower stem and re-bloom.

Repotting may be necessary every one to three years if the plant becomes root-bound or the media needs replenished.  Don’t be tempted to substitute the loose medium that came with your orchid with your favorite soil mix. Orchids like orchid mixes that drain well, otherwise they may decline to the point of no return.

Source: UTIA

Primates indispensable for regeneration of tropical forests

Moustached tamarins (Saguinus mystax) contribute crucially to the seed dispersal of the neotropical tree Parkia panurensis. Credit: Julia Diegmann

Primatologist and plant geneticists have studied the dispersal of tree seeds by New World primates.

Primates can influence seed dispersal and spatial genetic kinship structure of plants that serve as their food source. This is the result of a cooperation project of behavioral ecologist Eckhard W. Heymann from the German Primate Center (DPZ) with plant geneticists Birgit Ziegenhagen and Ronald Bialozyt from the Philipps-University Marburg. This study was funded by the German Research Foundation.

At the DPZ-field station Estación Biológica Quebrada Blanco in the Peruvian Amazonian lowlands, scientists studied how feeding, sleeping, and ranging habits of two species of New World monkeys affect the dispersal of the neotropical legume tree Parkia panurensis. For this, the researchers observed a group of Brown-mantled tamarins (Saguinus nigrifrons) and Moustached tamarins (Saguinus mystax), who jointly moved through home ranges in search of edible plants which included Parkia trees.

Fruits from these trees are pods that contain 16 to 23 seeds, each of which is surrounded by edible gum. The monkeys feed on the gum content of the pods and at the same time swallow the Parkia seeds which are later defecated intact in a different area.

During behavioral observations, researchers recorded the food intake of tamarins as well as the location of the Parkia trees that they visited. In addition, they collected faecal samples of the tamarins that contained seeds. "With the help of genetic analyses of the DNA found in the seed coat, which is of maternal origin, we could make an exact assignment of the corresponding "mother tree" for the seeds," says Eckhard W. Heymann from the DPZ. "This allowed us to determine how far Parkia seeds were dispersed by the monkeys."

In order to analyze the effect of seed dispersal by monkeys on a spatial genetic level, the scientists examined three different developmental stages of the trees. In addition to the seeds that contain the plant embryo, they collected leaves from young and mature Parkia trees in the home range of tamarins. "With the help of analysis from microsatellites, short repeated DNA sequences, we were able to identify genetic similarities of individual trees," says Heymann.

The analysis of the spatial genetic structure of the Parkia population revealed a significant genetic relationship of the plant embryos and young trees within a radius of 300 meters, which coincides with the distance within which most seeds are dispersed by the tamarins. For mature trees, the relationship was reduced to a radius of only up to 100 meters.

"In tropical rain forests, the seeds of 80 to 90 percent of trees and lianas are dispersed by animals. In addition to primates, birds and bats are the major animal groups that are responsible for seed dispersal," says behavioral ecologist Heymann. "For the plants, transport of their seeds is extremely important. As sedentary organisms, this is the only way that their offspring -- the embryos contained in the seeds -- can reach appropriate sites for germination and growth. Furthermore, this reduces the density-dependent mortality which occurs when the seeds fall under the mother plants," says Eckhard W. Heymann. Fruit-eating primates such as tamarins are therefore invaluable to the natural regeneration and diversity of ecosystems in which they live.

Source: German Primate Center