threadstalk speedwell

Family

Scrophulariaceae

Scientific Name

Veronica filiformis

Other Common Names:

whetzel weed

creeping speedwell

creeping veronica

slender speedwell

Habit

A trailing perennial with round creeping stems that grow up to 50 cm long and root at nodes. Plants form dense mats in turfgrass and flower from spring into early summer. Plants remain green through winter but some stalks will die back. Stems may become defoliated during hot and dry conditions but typically persist to sprout new leaves when weather conditions improve.

Leaves

Leaves are small (8 to 12 mm long) and round or kidney shaped and have sparse hairs. Lower leaves are opposite and leaves on the flowering stem are alternate. Leaf edges are notched with predominately rounded teeth. Leaves are borne from slender and delicate stems on short stalks (2 mm long). Upper and lower leaves are similar in size and shape.

Identifying Characteristics

The plant has a fibrous shallow root system with intertwining stems that root at nodes. Unlike most speedwells, plants typically lack seed pods or seed pods lack seed.

Flower Seed Head

Flowers are slighly smaller than a dime (8 mm diameter) and showy with split light blue and blue designs. Flowers are borne on long (up to 2.5 cm) stalks that arise singly from leaf axils on the upper stems.

Seed Fruit

Fruit is rare in North American plants and consists of a small (5 to 8 mm long) heart-shaped hairy pod. Seed are typically not produced in North America but common in Europe.

Where Found

Plants grow in lawns, ornamental areas, and winter grain crops. You can also find the plants in open waste places or home gardens but they do not thrive in areas where regular spring tillage is practiced. Plants may be found in many conditions but are best adapted to dry or sandy soils and shady lawns.

Growth Habit

Varies:

upright and nonwoody,

prostrate and nonwoody

Thorns or Spines

not present

Approximate Flower Diameter

Varies:

pencil,

dime

Dominant Flower Color

Varies:

white,

blue,

purple

Flower Symmetry

bilateral symmetry

Leaf Hairs

has hairs

Leaf Shape

oval

Leaf Arrangement

Varies:

alternate,

opposite

Leaf Margin

serrated

Leaf Structure

simple

Leaf Stalk

none

Stem Hairs

has hairs

Stem Cross Section

round or oval

Milky Sap

not present

Root Structure

Varies:

fibrous,

rhizomes present,

stolons present

Life Cycle

perennial

Ochrea

not present

Plant Type

Herb