Artist O'Keeffe would collect items in her local area and use them as subjects for modernist still life paintings. Leaves provided certain colour schemes that she felt worked well with her artistic style, as seen here with Autumn Leaves, Lake George.
Most followers of the artist will already be aware of her use of bones, in the likes of XXX and XXX. The specific colours here derived from the autumn season are browns, earthy reds and several shades of green.
O'Keeffe realised from an early age that nature had a way of choosing and balancing colours together in a way that most artists could learn from and even make use of in their own work. You will find examples of this with abstract artists like Mark Rothko, Jackson Pollock and earlier painters such as Paul Cezanne.
The artist is believed to have covered this subject 29 times between 1922 and 1931, with leaves being her version of Monet's haystacks in this case. That artist would keep the same group of objects and complete multiple works with them in a variety of light and time conditions.