Hamburger Bean
Mucuna species
Also known as Mucuna, Brown Hamburger Bean, Red Hamburger Bean, Ox-eye Bean, Horse-eye Bean
Markings and exact colorations may vary.
A rounded, thick drift seed with a dark hilum band around most of its edge. Use this entry when you can't tell brown from red.
- Typical size
- About 1 inch
- How often it turns up
- Uncommon
- Collecting
- Usually legal to collect
- Handling
- Safe to handle
Freely collectible.
No hazard.
How to tell it apart
- Rounded and thickly disk-shaped
- Dark hilum band running around most of the edge
- Seed coat can be dimpled or slightly wrinkled, not always smooth
- Color ranges from pale brown to reddish brown or almost black, so color alone does not settle the species
Found one?
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Commonly confused with
Sea PurseDioclea species
Sea purses often have a flatter top and a sharper, projecting edge where the hilum sits; hamburger beans are usually more rounded there. Shapes vary, so check more than one feature.
Grey NickernutGuilandina bonduc
Mature nickernuts turn gray. On a hamburger bean, the dark hilum band running around most of the edge is a better clue than a round shape alone.
Sea HeartEntada gigas
Sea hearts are flat and heart-shaped. Hamburger beans are round with a dark band around the middle.
Brown Hamburger BeanMucuna sloanei
Pick Brown when the face is plain brown; use the general Hamburger Bean entry if you can't tell.
Red Hamburger BeanMucuna urens
Pick Red when the face is maroon and speckled; use the general entry if unsure.
More sea beans in the field guide
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