Archive for the ‘science’ tag
These are some of my favorite plants. I’m a bit of novelty seeker and that carries over into my garden as well.
I’ve grown carnivorous plants as houseplants forever and they thrived and were gorgeous. I purchased some pitcher plants that are suited for outside growing in Houston. They haven’t died, but they aren’t thriving either. Now after attending a talk on carnivorous plants I know why.
The speaker has a plant store in Spring, PetFlyTrap.com I purchased some great plants from him that I have growing indoors right now. Mike Howlett works at Jesse Jones Park and can frequently be found there giving talks on carnivorous plants should you wish to learn more.
A carnivorous plant is one that attracts its own food, catches its food, and digests its food. There are over 600 known species. The earliest reference we have to them is in the 1578 book ‘New Herbal’. The Victorians, like me, loved novelty so it is not surprising carnivorous plants were popular in Victorian greenhouses. When it was rumored the first New World pitcher plants arriving, they lined up at the docks to get them. ( much like gadget geeks of today )
Carnivorous plants can be found just about every where that is not a desert. There are even water dwelling carnivorous plants. Two, the Australian water wheel and Texas bladderwort live on mosquito larvae. If you wish to keep mosquitoes from breeding in your bird feeder toss some in. ( I’m hoping to acquire some soon. ) It thrives and needs no care.
Most home growers cut off the flowers to save the plants energy. Myself I found the flowers to be exotic and loved them as much as the plants and let them be.
Carnivorous plants are very slow growing plants, buy the largest one you can find.
Carnivorous plants do use photosynthesis for energy, but use the bugs to provide nutrients not found in the poor soils that they grow in naturally.
To care for carnivorous plants:
1) Use distilled or rain water or filtered tap water. They are extremely sensitive to chemicals.
2) Carnivorous plants want acidic soil. ( Add vinegar if needed to the water. Or just mix peat into your soil mix. )
3) Try not to play with them. If you feed them bugs use bugs that are half the size of the traps.
4) They love humidity.
5) No fertilizer, ever. They will die.
6) Light needs vary by plant, most want full sun.
My problem is that it is too basic outside. And it hasn’t rained in forever so they’ve been getting tap water. I repotted them up and put them in a deep pot to hold the water. We’ll see if that works.
Allelopathy is the release of organic chemicals that help or harm plants growing nearby by a plant. What is really interesting is that these allelochemicals are not used by the plant except to influence other plants.
One of the best known cases of this happens with walnut trees. Walnut trees produce hydojuglone. When hydrojuglone is exposed to oxygen it causes anything from wilting to death in plants near the walnut tree.
While digging around the net learning about allelopathy I started to wonder just how smart plants might be and stumbled upon: Aspects of Plant Intelligence a paper published in the Annals of Botany in 2003
The more we learn about plants and the chemical signaling inside and sent out from the plant, the less like vegetables they appear to be.
The paper is very readable, you won’t need a science degree to dig through it and worth a read. You’ll not look at your plants the same way again.
It is believed that the previous two years of drought contributed to Tifton 85 grass producing cyanide gas that killed some cattle near Austin, Texas. Tifton 85 is a 1992 hybrid of Bermuda grass (Tifton 68 from Tifton, Georgia, US) and a South African grass, grown for its cold tolerance, high protein and digestibility.
The cattle died of prussic acid ( cyanide poisoning )
Cyanogenic glycosides in plants yield free hydrocyanic acid (HCN) aka prussic acid when plants are damaged.
Young plants and leaves of older plants contain dhurrin which can break down to release cyanide gas. This tends to be highest in young rapidly growing plants, especially those stunted by drought or damaged frost or other mechanical means. Heavy fertilizing with nitrogen in areas low in phosphorus is more likely to produce the gas. Treatment with 2,4-Dichlorophenoxyacetic Acid ( a broad leaf herbicide and pesticide ) also increases the risk.
It does decrease as plants die, decreasing slowest in drought stricken plants. The remaining acid may be concentrated in new shoots when regrowth begins. The darker the leaves, the higher the concentration.
Plants that can produce cyanide include: Apple, Apricot, Cherry, Peach, Elderberry, Flax, various sorghums, various grasses, hydrangea, lima bean, and others.
“We show that exposing tomato plants to some level of caterpillar herbivory will increase resistance for future plants—it’s sort of like a plant vaccine,” says Sergio Rasmann, a biologist at the University of Lausanne in Switzerland.
Rasmann isn’t the only one seeing this effect. In a similar study, Ann Slaughter of the Universite de Neuchatel in Switzerland infected Arabidopsis thaliana plants with a benign strain of the bacteria Pseudomonas syringae (PstavrRpt2). The offspring were more resistant to disease than control groups, which were not infected in the first generation.
How does pest resistance get inherited? Researchers point to epigenetic mechanisms, which regulate gene expression and can be passed from one generation to the next without any changes to DNA sequences. The studies suggest known epigenetic factors like DNA methylation and histone modification mediate these effects, and are among the first to demonstrate siRNAs act as an epigenetic mechanism in plant defense responses.