Extinct tress

Sigillaria was a lycopodiophyte tree that grew in the late Carboniferous period and became extinct 300 million years ago. It grew to 100 feet tall and had a twisted trunk 3-4 feet in diameter. It had long grass-like leaves that also grew in a spiral directly from its soft trunk. Rather than seeds, it reproduced by spores that hung down from its stems in cone-like structures. Botanists think their trunks were covered in photosynthetic material, so Sigillaria was probably green from its bottom to the top. It was a quick grower that probably died once it reproduced, but experts debate this. They’re found in the fossil record across the world including in Europe, Zimbabwe, China, Canada, and the United States. Sigillaria died out during the Westphalian to Stephanian climate change transition that dried up swamps and decimated many other tropical lowland plants.

A vascular tree in the Lepidodendraceae family, Lepidodendron grew in the Carboniferous period. This soft-trunked tree is often called “the scale tree” because its fossilized bark resembles reptile scales. In the 1800s, fossilized trunks were admired as giant reptile remains on display in traveling shows. Before they became extinct, lepidodendron grew in wet coal forests and was most likely soft, a bit like herbs, with the majority of its trunk clear of branches until the very tip. Scale trees reached over 100 feet tall and had a trunk diameter of 3-4 feet. Thousands of them grew tightly packed which made prehistoric forests very dense. This is another tree that reproduced via spores and experts think it died after reproducing. Lepidodendron became extinct 300 million years ago in the Westphalian to Stephanian climate change transition alongside Sigillaria, so we’ll never know for sure.

A more modern extinct tree is the St. Helena Olive, which only died out recently in 1994. This tree was not a true olive, but a relative of the jujube tree. It was endemic to St. Helena Island in the south Atlantic Ocean and is sometimes called the St. Helena mountain bush. However, by the 19th-century humans had all but destroyed their native woodland habitat as they made room for grazing goats. Only 15 of these endemic species were recorded in the wild in the late 19th century. The last wild bush died in 1994 after governmental efforts to save the species. The very last St. Helena’s Olive died in 2003 in cultivation.

This small, deciduous tree was endemic to the lowlands of western Moloka’i in the Hawaiian Islands. By the time it was discovered by western scientists, it was nearly gone. It’s thought that Polynesian settlers began deforesting the island from around 1,000 AD for agriculture. This widespread clearance destroyed its habitat.Kokia cookei had large, bright red flowers that would have attracted pollinators such as honeycreepers which are Hawaii’s nectar-drinking birds. Many honeycreepers are now extinct and the remaining species are endangered.Kokia cookei was presumed extinct in 1950, but a single seedling was found in 1970. Unfortunately this seedling died in a fire, but it had been previously grafted to the endangered Keokia kauaiensis plant. There are just over 20 of these plants alive today, but no full Kokia cookei exists.

Araucaria mirabilis belongs to the Araucaria genus. It’s an extinct conifer that used to grow in Patagonia, Argentina. Araucaria reached 330 feet in height and had a diameter up to 11 feet. Experts think they were the primary source of food for sauropod dinosaurs in the Jurassic period and the reason why sauropods evolved to have such long necks. This article from the Proceedings of the Biological Society explains more about this fascinating theory.Botanists are able to study this tree in depth because 160 million years ago a volcanic eruption buried an ancient forest. Its fossilized tree trunks are still upright in Cerro Cuadrado petrified forest in the Matilde Formation, Argentina. Many of their 4.9 inch diameter seed cones are fossilized too.This ancient extinct conifer was most likely the victim of climate change. As the moist areas dried up, it wasn’t able to reproduce and became extinct.