The best replacement for pickets is treated pickets.

The best alternatives to pickets are rated as following:
★★★★★  treated pickets
★★★★  cedar pickets
★★★  pressure treated pickets
★  pine pickets
★  treated pine pickets

Your alternative for pickets is not listed? Suggest!
Speaking about pickets, one probably shouldn't forget about iron fencing.

Other search terms related to pickets and their ratings are:
★★★★★ iron fencing
You have in mind a companion for pickets and it is not yet here? Propose!



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