Alternatively you can apply the sticky sap found inside flax (harakeke) leaves. This is said to have an antiseptic quality as well as purgative qualities. As an added bonus, the seeds of harakeke are edible and quite sweet when in their green or white state. Simply snap the pod and squeeze the seeds out.
Flowers also contain a delicious nectar, provided in abundance by the flax, a real energy boost in a survival situation.