Don’t mistake this autumn crocus for saffron! By Dr. Lew Feldman One of the first signs of the arrival of autumn is the appearance of autumn crocus (Colchicum autumnale), growing in the medicinal plants section of the Herb Garden at the UC Botanical Garden. This beautiful flower originates from the corm of a European endemic…
Garden Director Lew Feldman Unlike pollen, which is released by the flower only once, nectar is a renewable resource, often replaced daily, especially in long-lived flowers such as puyas. It is unusually sweet, a fact not lost on the Garden’s resident squirrels! Nectar is the main floral reward for bees and birds, and while sweet…
Garden Director Lew Feldman The Garden’s Mather Redwood Grove is part of the California collection and contains over 450 coast redwoods (Sequoia sempervirens). Given that the trees in the Grove are planted so densely, I am often asked how the understory plants, such as Oxalis oregana (wood sorrel), are able to capture enough sunlight for…
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…