2.5
Plants moving along mountain roads and trails
Did you know?
Some introduced plants are big problems such as lupin in Iceland. People like it in their gardens in many countries but it becomes invasive in the Arctic and displaces native plants. Nootka Lupin was also planted to prevent soil erosion in Iceland but is now having a large impact on native biodiversity.
Animals are getting to new areas too, both intentionally and by accident (e.g. fish and beavers, see story 5.6).
Invasive insect pest species can damage trees and make them more susceptible to fire thereby devastating huge areas of forest.
When you pick up a plant with some soil, it may have fungal pathogens in the leaves, harmful bacteria in the roots and pests in the soil – you don't just move the plant but lots of organisms too. At national borders, strong laws exist to prevent new diseases from coming into the country but harmful organisms travel from place to place inside countries too.
Particular invasive species include Colorado beetle, Japanese knotweed and floating pennywort.
Some plants are very clever, they have many ways of spreading their seeds very widely. Some are like parachutes blown on the wind, some have spikes to hitch hike on animals with fur and feathers, and some have exploding capsules to spread their seed.
As the Arctic gets warmer, and tourism and new transport routes increase, the risk of introductions of pest species is greater and the conditions will be better for them to become established.
Get Active!
Exploding Seeds Experiment
You will need:
Seed dispersal is essential for many plants' survival and it can be done in a myriad of ways. Some plants disperse their seeds by having hooks on the seeds in order to allow animals to transport them, others are dispersed by wind or rain or by animals eating fruits that surround the seeds for them to excrete later. One of the most fascinating ways of dispersing seeds however is by exploding seed pods.

This experiment will simulate how seed pods can explode to maximise their seed dispersal.
Instructions
Fill a balloon with birdseed, using the funnel. Approximately 50g of birdseed can be used for each balloon. Try not to purchase seeds that have pumpkin or sunflower seeds in as this could block the funnel.
Blow up the balloon to increase tension and pressure inside the 'seed pod'.
Tie up the balloon and take it outside in an open area.
When outside, put down a table cloth or large mat to catch the seeds when the balloon explodes.
Hold the balloon over the table cloth/mat and point it away from you. Use a sharp pencil to explode the balloon. Make sure you pick up the plastic pieces from the balloon on the ground, but leave the seeds where they are.
Follow-Up Questions
Did all of your seeds fall onto the table cloth/mat?
How far did your farthest seeds travel from where you are standing?
Was there a difference in size between the seeds that travelled furthest and the seeds that stayed close?
Do you think this is the most efficient dispersal technique for seeds?