Dr. Lew Feldman, Garden Director Horsetail (Equisetum telmateia) An invasive weed, but also useful in many ways! Horsetail (Equisetum telmateia) is found throughout the Garden, generally as an invasive, aggressive weed. But what truly distinguishes horsetail is that it is rich in the mineral silicon (silica), which contributes to cell wall rigidity and to the…
Dr. Lew Feldman, Garden Director The onset of fall brings cooler weather, shorter days, and brilliant color seen across a range of plants. We are presented with stunning displays of orange, yellow, red and purple leaves. What causes the foliage to change color? The environmental cues that make a plant ready for winter are typically…
Dr. Lew Feldman, Garden Director In this edition of IGYA we will consider bark, which is the outermost layer of trees, woody shrubs and vines, and which can be thought of as the “skin” of a woody plant. Bark is essential for a tree’s survival. Bark has an important role in protecting the plant from…
Dr. Lew Feldman, Garden Director One of the questions that students frequently ask me is what is the difference between “hard” and “soft” woods. The answer, however, is not straightforward because the terms hardwood and softwood do not necessarily relate to the density or hardness of the wood itself. Rather, the wood type depends on…
Dr. Lew Feldman, Garden Director Water Transport How do plants “drink” water? In this issue of IGYA we consider the process of water movement in plants, over great distances, such as to the tops of tall trees, without the aid of a pump. To appreciate how plants carryout this great feat, we need to consider…
Dr. Lew Feldman, Garden Director In previous IGYAs, we discussed two major plant signaling molecules: auxin and gibberellin. In this third write-up on plant growth and development controls, we will consider the molecule ETHYLENE, agriculturally and commercially the most important plant signaling molecules. Unlike auxin and gibberellin, which are moved about the plant via internal…
Dr. Lew Feldman, Garden Director In a previous IGYA we began discussing the regulation of growth and development in plants via signaling molecules and focused on the naturally occurring compound known as auxin. In this write-up, we will consider a second group of signaling molecules called the gibberellins (abbreviated GA). As with auxin, in discussing…
Dr. Lew Feldman, Garden Director Over the past few weeks I have received many inquiries and questions about the effects of wildfires, and in particular, smoke and ash, on plants. In the western US fire has shaped plant communities for more than 300 million years and thus fire is regarded as an important factor in…
Dr. Lew Feldman, Garden Director In this issue of IGYA we want to begin a discussion of how plants control their growth and development. In particular, I want to consider how our understanding of these controls relates to common horticultural practices. As in animals, plants too have signaling molecules which occur in extremely low concentrations…
Dr. Lew Feldman, Garden Director One of the more common and challenging activities for both indoor and outdoor gardeners is changing the location of a plant, which is sometimes necessary when a plant has become too large for a particular location, or, for indoor horticulturists, perhaps associated with rearranging the layout of a room. And…