Is it safe to use pine straw under a bird feeder? What is the difference between using wheat straw and pine straw? Right now I am using natural wheat straw but the problem is that it gets dirty fast especially after a week of rain then something grows out of it that looks like fungus or mold. What I do is every week I add a noticeable higher layer of wheat straw on top of the old so the birds can't eat from the old wheat straw and do this every week for a month then clean all of it and replace it with new wheat straw. The bad thing about this is that the natural wheat straw can be expensive. I found a place that sells pine straw which costs way less. They say it's natural pine straw. Do most places sell natural pine straw with no chemicals added to it? And why don't they advertise it as natural pine straw? Will mold or fungus also grow from the pine straw? Can pine straw cause plants, grass, or weeds to grow? The pine straw costs way less but I have to make sure it's 100% safe and really natural pine straw. This is why I am asking these questions here.