First of all, you’d better get a rune axe, even though you don’t have 40 attack level, you could still be able to use it to cut tree, just put it in your inventory.
For Woodcutting 1-15, you can only spend 10 minutes to finish the job. Just drop these logs. No one will buy!
For woodcutting 15-30, you could cut oak tree which near Lumbridge; drop these logs as well, till you get level 30!
For woodcutting 30-45, you can cut willow which can be found in Lumbridge, each log sells for 20 coins, and it will take 2~3 hours to get your woodcutting level to 45;
For woodcutting 45-60, you may cut maple logs, but that's only for member account, you d better get to be member to cut this tree, price of each maple log sells for 30-40 coins;
For woodcutting 60-75, you may cut Yew tree which is located under falador city,
Or member can get it in left hand of Catherby City, each Yew log sells for 300 coins;
After you get Woodcutting level 75, the legend of magic logs can be cut, but only for members, and at least you must use rune axe, Price for each magic log is 1K coins,
What a nice price!
Now, you can see for non-member account, Yew logs is your best choice for making gold. For getting rich in runescape, you will need to spend more time on Cutting!

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