Biodiversity Plants

Dutch Elm Disease

In the last 100 years, Dutch Elm disease, has killed millions of Elm trees. This disease is caused by a tiny fungus, which is spread by the elm bark-beetle.

The fungus sticks onto the little black beetle, and is carried to new elm trees. The beetle eats its way through bark, and the fungus is left behind inside the tree. The beetle also lays eggs inside the elm tree, which hatch into burrowing larvae.

Dutch Elm Disease

The water conducting vessels (xylem) become blocked, and so water cannot flow to where it is needed.

Dutch Elm Disease - burrows made by beetle larvae visible
If the Elm's leaves curl and turn yellow in the summer, it is suffering from Dutch Elm Disease. The elm tree will later die.

Large areas of the countryside no longer have elm trees because of this disease.

	Dutch Elm Disease
	In the last 100 years, Dutch Elm disease, has killed millions of Elm trees. This disease is caused by a tiny fungus, which is spread by the elm bark-beetle. The fungus sticks onto the little black beetle, and is carried to new elm trees. The beetle eats its way through bark, and the fungus is left behind inside the tree. The beetle also lays eggs inside the elm tree, which hatch into burrowing larvae.

	The water conducting vessels (xylem) become blocked, and so water cannot flow to where it is needed.
		If the Elm's leaves curl and turn yellow in the summer, it is suffering from Dutch Elm Disease. The elm tree will later die. Large areas of the countryside no longer have elm trees because of this disease.