Red hailstone (Thladiantha dubia)

red hailstone leaves with one yellow flower

 
 

Red hailstone (also known as golden creeper) is a perennial vine in the cucumber family that can grow up to 18 feet long. It has tendrils that help it grow over other plants and up into trees. Red hailstone has separate male and female plants. In Minnesota, only male plants have been found (as of 2023), so fruits have not been observed in the state. Red hailstone can spread from underground potato-like tubers that break off and produce new plants. The tubers can also float, spreading the plant along waterways.

Description

Appearance

Red hailstone is a perennial vine with heart-shaped leaves, tendrils, and yellow tubular flowers. The underground portions of the plant live from year to year, but the stems and leaves die back each winter.

Leaves and stem

Leaves are heart shaped and alternate (come off the stem one at time at each leaf node). Leaves and small teeth along the edges. The leaf is on a stalk that can be up to 2.5 inches long. The leaves themselves can be up to 6 inches long by 4 inches wide. Opposite the leaf is a curly tendril. Leaves, stems, and tendrils are all hairy. Stems can grow up to 18 feet long and grow over other plants or up trees.

Flowers

Flowers are yellow, tubular or bell-shaped, and have five petals.

Seeds and reproductive structures

Red hailstone has separate male and female plants. In Minnesota, only male plants have been found (as of 2023), so fruits have not been observed in the state. The fruits are red with white hairs and can be 2 inches long. Red hailstone can reproduce vegetatively from underground potato-like tubers that break off and produce new plants. The tubers can also float spreading the plant along waterways.

Rhizomes and/or roots

Red hailstone roots can form underground potato-like tubers that break off and produce new plants.

Biology

Red hailstone is a perennial vine. The underground portions of the plant live from year to year, but the stems and leaves die back each winter. Red hailstone has separate male and female plants. In Minnesota, only male plants have been found (as of 2023), so fruits have not been observed in the state. Red hailstone can reproduce vegetatively from underground small potato-like tubers that break off and produce new plants. The tubers can also float, spreading the plant along waterways.

Origin and spread

Red hailstone is native to Asia. It was likely introduced to the United States for ornamental purposes.

Refer to EDDMapS Distribution Maps for current distribution.

Don't be fooled by these look-alikes

  • Bur cucumber, Sicyos angulatus (native) – the flowers are white to white/green, the fruit is 0.5-1 inch long and green to brown with spines, leaves are more lobed than red hailstone leaves.
  • Wild cucumber, Echinocystis lobata (native) – leaves have five lobes and pointed tips, the flowers are white, and the fruit is green with spines.
  • Japanese hops, Humulus japonicus (invasive) – also grows and spreads along waterways, but has leaves that are somewhat hand-shaped with have five to seven lobes, while red hailstone leaves are heart shaped.
  • Wild grape, Vitis riparia (native) – Wild grape leaves have strongly toothed edges and the leaves are more lobed than red hailstone’s heart shaped leaves with very finely toothed edges.
  • There are many similar looking plants in the cucumber family that you may see growing in gardens such as pumpkins, squash, zucchini, and cucumbers. The familiar fruits of all of these vegetables look very different from the red fruit of red hailstone.
 
Regulatory classification

This species is a Minnesota Department of Agriculture Prohibited Noxious Weed on the Eradicate List meaning that the above and below ground parts of the plant must be destroyed. Additionally, no transportation, propagation, or sale is allowed.

Threat to Minnesota
  • Can displace native species.
  • Can be difficult to control in agricultural fields and gardens.
  • Red hailstone is difficult to control once established because it produces underground tubers.
What you should do

One way that invasive plant seeds and fragments can spread is in soil. Sometimes plants are planted purposefully. You can prevent the spread of invasive plants.

PlayCleanGo: Stop Invasive Species in Your Tracks

  • REMOVE plants, animals and mud from boots, gear, pets and vehicles.
  • CLEAN your gear before entering and leaving the recreation site.
  • STAY on designated roads and trails.
  • PLANT non-invasive species.
Native substitutes
  • Wild grape (Vitis riparia)
  • Virgin’s bower (Clematis virginiana)
  • Wild cucumber (Echinocystis lobata) and bur cucumber (Sicyos angulatus) – note that both of these native vines can become very abundant in some years so may not be the best choice for a garden setting.

 
Control methods

Mechanical control can be done by cutting or pulling the plant by hand. Be aware that tubers are likely to break off and remain in the soil and create new plants so mechanical control alone may not be enough. Follow Minnesota Department of Agriculture noxious weed disposal guidance for the pulled plants.

Herbicide control can be done using systemic herbicides which are taken up by plants and move within the plant, which can kill leaves, stems, and roots. Apply herbicide containing glyphosate or triclopyr to the leaves of red hailstone. August through October are likely to be the most effective times for herbicide application. 

Reporting

Report new occurrences by submitting a report through EDDMapS, emailing Report a Pest, calling Report a Pest (1-888-545-6684), or contacting your local county agricultural inspector.

Resources

Back to top