Seed Dispersal http://www.newtonsapple.org.uk/se ed-dispersal-by-fire/
Seed Dispersal
General Seed Dispersal Methods Wind Gravity Float/Water Hitchhike /Animals Force/Explode
Floating Seeds
Coconut Palms The mezocarp of the coconut Drupe is a spongy material called Coir that allows it to float sometimes for several months
The world's largest been pods come from woody vines or lianas of the genus (Entada). They are native to the rain forests of the Old and New World tropics. The largest species is called the sea heart (E. gigas), and the pods may be 5 feet long. The woody, heart-shaped seeds of Entada gigas are carried by torrential rains into rivers and eventually into the sea where they often drift to the shores of distant continents and islands.
Water Lily Nymphaea Sp. The lotus water lily pod is designed to float (upside down if possible) and slowly disperse seeds along the pond s edge. Water lily pods
Desert Seeds- Rough seed coats requiring scarification Palo verde seeds requiring scarification Blue Palo verde Desert shrubs growing along regular water flood Channels where they are likely to have regular access to rainfall runoff
Wind Dispersed Seeds Milkweed seeds are the classic windblown seed
Wind Silky Parachutes Close up of Common Salsify seed head
Thistle
Thistle seeds blowing away from the seed head
Tragopogon dubias Common Salsify Has Seeds that blow in the wind like a dandelion
Dandelion Taraxacum officinale
Wind Winged Seeds White serraya Hopseed Javan cucumber Maple
Tipping Capsules Tossed from cups Instead of an exploding capsule some plants perch their seeds in cups at the end of tall stems to be tossed or flung as the stems sway with a breeze Water horehound - Lycopus Red Campion seed head - Silene dioica Wild columbine Aquilegia candensis
Animal Internal Tomato, plum, raspberry, grape have brightly colored and succulent fruits which contain seeds with indigestible coats which allow the seeds to pass through the animal undamaged
Mistletoe has an extremely sticky seed that often has to be scraped off of the bird s bill after landing on a branch.
Hitchhiking Seeds
Seeds with barbed hooks Stick tights Burdock Beggars ticks
Tumbleweed Russian thistle Salsola iberica Plants dry up and break off at the base and disperse seed while rolling along as a tumbleweed Originally from Russia it has become one of the most common and troublesome weeds in N. America
Exploding seeds Touch-me-not
Shot From Pods Jewelweed pods Witch hazel pods Creeping wood sorrel Oxalis is known to shoot it s seeds 10 feet
The Seed Eliasome and Ants Ants store seeds with nutritious Eliasome in their nests which once the eliasome are consumed, the seeds are abandoned in the ant s trash heap where they have a perfect well aerated subterranean place to then germinate.
Erodium cicutarium Example of Seeds that actively Burrow into the ground
Giant Sequoia The Chicory helps to distribute the giant Sequoia by both gathering up and storing large caches of the cones and by eating the fleshy outer parts that help to release the oatmeal sized little seeds within. Douglas squirrel Chickaree Green cones
Serotiny response to environmental trigger Fire breaks down the resins previously holding the Jack pine cone tightly closed. The cone then opens releasing the seeds into a less competitive environment
Types of Serotiny Death of the parent plant or branch (this death can be caused by fire). This form of serotiny has been termed necriscence. Wetting (hygriscence) Warming by the sun (soliscence) Drying atmospheric conditions (xeriscence) Fire (heat, essentially: pyriscence) Fire followed by wetting (pyrohydriscence)
Lodgepole saplings germinating after a fiire
Serotiny Serotiny is an ecological adaptation exhibited by some seed plants, in which seed release occurs in response to an environmental trigger, rather than spontaneously at seed maturation. The most common and best studied trigger is fire, and although serotiny is often used to refer to this specific case, this is an overgeneralization.
Pyrohydrescence Banksia seed with seed separator in tact In pyrohydrescence the follicles containing 2 seeds are opened by fire but the seed separator remains intact until cooling or in some cases wetting occurs before the 2 outside seeds are released
Smoke The Emmenanthe penduliflora has a bank of seeds stored in the soil which only germinate in response to smoke shock. They will only germinate in response to chemical signals emitted by smoke and charred wood.
Smoke Whispering Bells Emmenanthe penduliflora would be an excellent additive to seed mixtures for erosion control and fire following seed mixture, if you can find it.
What We Need to Know About Seed Dispersal Like pollination plants have figured a way to employ different ways to send their offspring into the world without competing with themselves Along with physical characteristics that allow them to roll, float, explode, or blow in the wind they have learned to trick (employ) animals to move and distribute their seed for them. We need to be able to cite at least one or two examples of each type of seed dispersal method including the ways plants interact with animals to do their bidding
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