Ulmus laevis

The white elm is a very large tree.

It loves to grow near rivers. It can stay in wet ground for a long time. Floods help it spread its seeds.

This tree has many names. Some call it the spreading elm. It can grow more than 30 meters tall. It has a wide shape.

Its leaves are thin and light. They look almost like paper. The leaves fall off in the autumn.

Small flowers grow in the spring. These flowers are cream-colored. They come out before the leaves.

Many butterflies love this tree. It helps them live and grow.

It is a special home for them.

The European white elm is a very large tree.

It can grow over 30 meters tall. It often has an untidy shape. This tree loves to grow near rivers. It can live in wet ground for over 100 days. Floods help the tree spread its seeds.

In the spring, cream-colored flowers appear. These flowers come out before the leaves. The leaves are thin and light. They feel almost like paper. These leaves fall off in the autumn.

This tree has a special bark. It starts out smooth. Later, it breaks into grey scales. In old age, the bark has deep cracks. The roots are shallow and wide. They form big parts around the base. We call these parts buttresses.

Many insects like this tree. One butterfly, the white-letter hairstreak, uses it to live. Some people plant these trees to help butterflies. The tree grows very fast in moist soil. It is a big part of river forests.

The European white elm is a large, spreading tree.

It is also called the fluttering elm or the Russian elm. This tree is native to many parts of Europe. It grows from France to Finland. It also grows east past the Ural Mountains into Kazakhstan. You can even find small groups of them in Spain and the Caucasus. These trees love to live in alluvial forests. These are forests found near rivers. Because they love water, they are rarely found above 400 meters high.

This tree has a very special way of growing. It can handle ground that is wet and lacks oxygen for over 100 days. This makes it one of the few elms that can live in waterlogged soil. The tree uses floods to spread its seeds. When rivers flood, they carry the seeds to new places. The seeds are small winged samaras. They are less than 15 millimeters long. These seeds have a high germination rate. In some places, as much as 60% of the seeds will grow into new trees. This helps the species spread along river paths.

Scientists have studied this tree for a long time. A man named Pallas first identified it in 1784. He named it Ulmus laevis in his book, Flora Rossica. In the United Kingdom, the tree is quite rare. Some people think it might be native there. Others think it was brought by people long ago. The first recorded specimen in a garden was in 1838. It was found at Whiteknights Park in Reading. This tree is a close relative of the American elm. However, it looks different because its branches are more untidy.

There are many interesting facts about how the tree looks. It can grow more than 30 meters tall. The trunk is usually less than 2 meters wide. The bark changes as the tree gets older. It starts out smooth and young. Later, it breaks into thin grey scales. In old age, the bark has deep cracks. The leaves are thin and feel like paper. They are often translucent, which means light shines through them. The flowers are cream-colored and appear in early spring. They grow in clusters before the leaves even arrive.

Even though the tree faces hard jobs, it is very useful. Many insects rely on it to live. For example, the white-letter hairstreak butterfly uses it as a host. Because of this, people now plant these trees to help butterflies.

The tree also has a trick to stay safe from bugs. It contains a substance called alnulin in its bark. This chemical makes the tree unattractive to certain beetles. While Dutch elm disease can hurt these trees, they are often safe in western Europe. This is because the beetles do not like them as much as other elms.

The European white elm, known scientifically as *Ulmus laevis*, is a large deciduous tree. It is also called the fluttering elm, spreading elm, or Russian elm. This species is a vital part of alluvial forest ecosystems. These are forests located near rivers and floodplains. The tree is highly specialized for these wet environments. It can survive in waterlogged, anoxic ground conditions for over 100 days. This ability to tolerate low oxygen in the soil sets it apart from many other trees.

The tree has a very specific way of growing and spreading. It relies on river floods to move its seeds to new locations. The fruit of the tree is a winged samara. Each samara is less than 15 mm long and 10 mm wide. Inside the samara is a single round seed about 5 mm in size. These seeds have a high germination rate. In Serbia, studies showed a rate of 45% to 60%. The tree is also protandrous, meaning its male parts mature before its female parts. This helps manage how the tree pollinates itself.

*Ulmus laevis* has a distinct physical structure. It can grow to a height and breadth of more than 30 meters. The trunk is typically less than 2 meters in diameter at breast height. Its branch structure is often loose and untidy compared to other elms. This gives the tree a unique silhouette, especially in winter. The leaves are simple and ovate, measuring less than 10 cm long. They are thin and almost papery, making them very translucent. A key way to identify them is that the leaf veins do not divide from the central vein to the margin.

History shows that scientists have long studied this species. Peter Simon Pallas first identified the tree in 1784. He published his findings in a work called *Flora Rossica*. In the United Kingdom, the tree's origins are somewhat mysterious. It is rare in the UK, but its random distribution makes some experts wonder if it is native. The first reported specimen in cultivation was in 1838 at Whiteknights Park in Reading. Some historical records used the name *Ulmus effusa* to describe it. This name was used in botanical dictionaries throughout the early 1800s.

The tree is most commonly found along major rivers like the Volga and the Danube. It rarely grows at elevations higher than 400 meters. This is because it is a riparian species, meaning it lives on river banks. In Spain, the population is considered a relict population. This means it is a leftover group from a much larger past presence. However, the species faces threats in some areas. Habitat destruction and flood control schemes can harm the trees. These schemes stop the floods that the tree needs to spread its seeds.

One of the most interesting things about the white elm is its relationship with pests. Many elms have been destroyed by Dutch elm disease. While *Ulmus laevis* lacks innate genetic resistance, it is rarely infected in western Europe. Research in Spain suggests this is due to a chemical in the bark. The bark contains an antifeedant triterpene called alnulin. At a concentration of 200 μg/g, this substance makes the tree unattractive to bark beetles. This chemical defense helps the tree avoid the primary carriers of the disease.

Finally, the white elm plays a major role in local biodiversity. It is a vital larval host plant for the white-letter hairstreak butterfly. Because many native elms died from disease, this butterfly lost its food source. To help, groups like Butterfly Conservation are planting white elms to restore populations. This creates a connection between forest management and insect conservation. The tree's ability to grow rapidly also makes it useful in certain landscapes. In moist soil, a 13-year-old tree can increase its trunk width by 4 cm every year.