Boundary Invasive Species Society
(Linaria dalmatica) and
Dalmatian toadflax is an aggressive weed that spreads quickly and degrades habitat. It is commonly found it pastures and along roads and trails. It is toxic to livestock.
Yellow toadflax can reduce crop yields and create dense mono-cultures in pastures and along roads and trails. It is commonly found in wildflower seed mixes. Do not purchase seed mixes unless all contents are listed.
Dalmatian toadflax (Linaria dalmatica) is an escaped ornamental plant that is native to the Mediterranean areas of Europe and Asia. It is toxic to livestock but because it is so unpalatable reports of poisoning are rare. It is an aggressive plant that can spread quickly.
Yellow or Common toadflax (Linaria vulgaris) is an escaped ornamental plant that is native to most parts of Europe and Asia. It is mildly toxic but it is not considered to be poisonous to livestock.
Dalmatian toadflax is a perennial. It is a prolific seed producer and it has an extensive, creeping root system. The roots can go 3 m down and 4.5 m laterally. It has heart shaped waxy green leaves. It grows up to 1.2 m tall and has bright yellow flowers with an orange spot on the lower lip.
Yellow toadflax is a perennial with long narrow leaves. It has a creeping root system and it also spreads by seed. It grows up to 0.6 m tall. It has yellow, snapdragon-like flowers.
There are 7 different bio-control agents for Dalmatian and yellow toadflax in B.C. We have a number of them established here in the Boundary. For the most part toadflax is under bio-control in the Boundary. Some herbicide treatment of toadflax was done in the area of the Rock Creek Fire. The fire killed a number of bio-control insects and until the populations rebuild it is important to stop the spread of invasive plants. Repeated hand pulling over many years can be effective. Intense, repeated cultivation in crop situations can be effective. Remember to clean your equipment before moving it as root fragments can sprout new plants.
Both Dalmatian and yellow toadflax are provincially designated as noxious under the Weed Control Act. Which means you must control it if it is on your property.