Source Of Denial is one of the new Runescape achievements which is actually really easy to achieve and can be done in 1 minute. Basically you need to pick fruit from a Sq’irk tree in the Sorceress’s Garden without stopping and it awards 10 runescore points. One has to start right beyond the entrance gate and pick a fruit from the tree without stopping. Running is imperative, and it is done most easily in the winter garden.
Go winter and look for this position:
When you see the spirit click on the sq’irk tree and let your pixels do the running – as you near the tree click on it again so it picks it straight up.
Sometimes you will get the message “someone’s actions have disqualified you from completing the source of denial achievement”. That is normally you, sometimes you can get through without the elementals firing off the teleport spell as you are behind a wall, so you can still pick the sq’irk but it will not count for the achievement. Just keep trying and you will get it eventually.
The elemenatals can also get out of sync when they catch you or someone else so look out for that too when following the above guide.