Botanizing New Zealand: Plant Identification Down Under

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White or Grey Mangrove: Avicennia marina.

Botanizing New Zealand
Plant Identification Down Under

      As a plant geek, every travel adventure is a botany expedition, an opportunity to see exciting new plant species, some that fit familiar plant family patterns, and some that are entirely new. As the author of Botany in a Day: The Patterns Method of Plant Identification, it is also an opportunity to see how well my book applies to places and plants I've never seen before. The book emphasizes plant families from my home turf in the northern latitudes, or the "frost belt" of North America. However, other people have used Botany in a Day for plant identification everywhere from Europe to Africa to Panama. I've traveled extensively in western North America and a little bit in Canada and Mexico, and not much beyond that. Thus it is truly exciting to travel to the southern hemisphere and geek out on plant life of subtropical New Zealand.

Mangroves
      I couldn't help but get swept up by the mystery of the green seeds sprouting on the beach at Orewa, the very first day I arrived in the country. At first glance, it appeared that the seeds were quadcotyledons instead of dicotyledons, since there seemed to be four seed leaves, but upon closer inspection, it was apparent that the two seed leaves were sharply folded around each other to look like four separate seed leaves.

      As I continued to explore the beach, I found seeds that were sprouting roots, and I thought it most remarkable that any seed could survive being tossed around in the salty surf, sprouting leaves and roots in the hopes of somehow taking root along the shore. Then I saw a specimen with well-developed stilt-like legs (shown here) and immediately hypothesized that these must be the famous mangrove trees (not covered in Botany in a Day) that help protect shorelines from the ravages of tropical storms and tsunamis. My hypothesis was quickly confirmed by a passing Kiwi woman, who explained that the trees grew in the nearby estuary. I checked them out. There were shrubs growing in the water, and they had regular trunks, not the obviously stilt-like roots propping them up from all sides as I had seen in photos. I would not have recognized them if I had not been trying to solve the mystery of the seeds. Other mangroves growing in other estuaries were more tree-like, but none had the prop-like stilts. (Scroll down for more photos.) Unraveling the mystery of the seeds on the beach and discovering the mangrove trees was immediately one of the great highlights of the New Zealand adventure!

White or Grey Mangrove: Avicennia marina. Isolated Since the Age of Dinosuars
      I was especially curious about New Zealand plant life because the islands broke off from the mainland 83 million years ago, during the age of dinosaurs, and before the rise of mammals. As a result, the islands originally had no mammals, and one might reasonably surmise that the plant life would be all but unrecognizable after 83 million years of isolation. However, the natural history of New Zealand is much more complex than that. Geologically, the islands largely eroded away and sank into the ocean 35 million years ago, wiping out many of the original plant and animal species before collision of the Pacific and Australian plates initiated new uplift and volcanic activity.

      On the other hand, many species of plants and birds naturally found their way to New Zealand from Australia and other South Pacific islands, before and after that time. For example, New Zealand has two species of native bats, the short-tailed bat (Mystacina tuberculata), which is thought to have arrived there 35 million years ago, and the long-tailed bat (Chalinolobus tuberculatus), which seems to have arrived there much more recently. Even if only one plant or bird or bat somehow found its way to New Zealand every 50,000 or 100,000 years, that would still add up over time. Nevertheless, New Zealand remained one of the world's most isolated ecosystems until it was first colonized by Polynesian peoples 800 - 1,000 years ago, and subsequently discovered and colonized by Europeans in the 1700s and 1800s.

White or Grey Mangrove: Avicennia marina.       I knew there would be some recently introduced species, but I wondered if my book would be so out of place as to be functionally useless in such an alien environment. As it turns out, however, much of the flora of New Zealand is very familiar, mostly due to the intentional and accidental introduction of foreign crops, ornamental plants, and weeds from around the world. Sadly, the majority of New Zealand was intentionally cut, burned, plowed, and replanted with foreign species, entirely re-writing the ecosystem. Native species are still prevalent across the country, but often not dominant.

      From my observations, Botany in a Day is especially useful for identifying plants around areas of human settlement, particularly most cultivated plants and weeds with showy flowers. Even if a person is chiefly interested in native plants, it is still helpful to learn these introduced plant families first to develop a solid background in plant identification, which makes it easier to approach other new and unfamiliar plant families. Each of the sections below summarizes my discoveries and experiences botanizing around New Zealand, from common global weeds to new plants from familiar families, as well as entirely new and unfamiliar species and families.

      Please send me an e-mail to report mistakes or to inquire about purchasing high resolution photos of these plants.

Botanizing New Zealand
1. Intro and Mangroves | 2. Introduced Weeds | 3. Cultivated Flowers
4. Introduced Trees & Shrubs | 5. Podocarps & Araucarians | 6. Native Flowers, Shrubs, & Trees

White or Grey Mangrove. Avicennia marina. Mangrove seeds float out of the estuary and wash up on the beach. They somehow survive salty seawater as well as the blistering hot sun, laying completely exposed, roots and all, on the beach. Nevertheless, few will ultimately survive outside the estuary.

White or Grey Mangrove. Avicennia marina. Mangroves seedlings successfully root in the brackish water of the estuary. Mangroves were once thought to belong to the Verbena Family, but then separated into their own family, and now considered part of the Acanthus Family.