What does Matt tend and water at the beginning of The Sign of the Beaver?

An examination of the first chapter will give you the
answer that you are looking for. As the novel opens, we are told that Matt has just been
left by his father in the middle of the forest to look after their plot of land and home
whilst his father returns to civilisation to collect Matt's mother and sister, who will
come and live with them. Matt and his father have been living in the forest for some
time, making their house and clearing land for farming. They have also planted some
crops. As Matt is left by himself, it is vitally important that he tends to the crops
that they have left. Note what the first chapter tells us about these
crops:

Behind
the cabin were the mounds of corn he had helped to plant, the green blades already
shooting up, and the pumpkin vines just showing between the stumps of
trees.

Thus we know that the
two crops that Matt has to look after and that he tends and waters are the corn and
pumpkin vines that he planted with his father before his father left him to go and
collect the rest of their family.