I am going to say that this photo is from around 1910 to 1920. I could be wrong on this, as the styles are very general and really could show any time period in at least certain places in the USA from some time in the 19th century to up to the 1930s.
However the group are posed relatively informally and are clearly not in a studio, so I'm not going for the 19th century.
The doors of the house likewise do not strike me as 19th century - and indeed you may well be able to get a pretty accurate date of the doors by comparing them to doors on architecture based websites. Of course, once in place a door might last decades. The family strike me as poor, and so the clothes they are wearing may well not be the most fashionable. Likewise that stool may be far from new.
There is clearly no father in this photo, he might be taking the photo, might be at work or might be dead or elsewhere, almost certainly it shows a mother and 4 children, 2 girls and 2 boys, and I think the age order is fairly obvious too - all particular family order should make it relatively easy to at least eliminate a lot of possible family groups from your tree.
Hopefully other folk will have some helpful comments.
Regards
Neil