Polygonum delopyrum facts for kids

Polygonum delopyrum, also known as the fringed jointweed or hairy jointweed, is a special plant found only in Florida, USA. When a plant or animal is found only in one specific place, it's called endemic. This plant grows in sandy areas, especially in pinelands, which are forests mainly made up of pine trees. You can find it in the central and southern parts of Florida, usually in places that are less than 50 meters (about 164 feet) above sea level.

What Does the Fringed Jointweed Look Like?

The fringed jointweed is an annual plant, which means it lives for only one growing season. It can grow quite tall, up to 110 centimeters (about 3.6 feet)! Its stems branch out from near the bottom.

Leaves and Flowers

The leaves of this plant are long and narrow, like thin lines. They can be up to 5 centimeters (about 2 inches) long. Along the edges of the leaves, you'll find tiny, flexible hairs called cilia. These hairs give the plant its "fringed" or "hairy" name.

The flowers grow in a cluster called an Inflorescence, which can be up to 45 millimeters (about 1.8 inches) long. The flowers are white. Some flowers have both male and female parts, which are called hermaphroditic. Other flowers have only female parts. After the flowers, the plant produces small, brown, triangular seeds called achenes, which are about 4 millimeters long.

How Did This Plant Get Its Name?

The scientific name of a plant can sometimes change over time as scientists learn more. The fringed jointweed is a good example of this!

A Name Change

This plant was first described in 1856 by a scientist named Carl Daniel Friedrich Meissner. He gave it the name Polygonella ciliata. Later, another scientist, John Kunkel Small, placed it in a group of plants called Polygonella.

However, in 2015, scientists used new methods, like studying the plant's DNA (this is called molecular phylogenetic studies), to understand how different plants are related. They found that the Polygonella group actually belonged inside a larger group called Polygonum.

Because of this, the plant needed a new name in the Polygonum group. The name "Polygonum ciliata" had already been used for a different plant, so they gave our fringed jointweed a new, unique name: Polygonum delopyrum.

Similar Plants

There's another plant called Polygonum basiramia that looks very similar to Polygonum delopyrum. Some scientists used to think it was just a type of Polygonum delopyrum. But now, many plant experts, including those who created the Flora of North America and Plants of the World Online, consider Polygonum basiramia to be its own separate species. The main difference is that Polygonum basiramia usually branches out from the ground level or even below it.