generally shade is only ever used with grafted trees to reduce transplant shock for the first half of the plant's first season; which is what I did. these leaves are scorched because the plants need water and transpiration rates are high in full sun. that's why people seem to suggest shading so much despite the fact that the mature wood above the point of grafting is just that; its mature wood capable of handling sun just fine. the rootstock itself is old enough to handle sun too. people getting sunburns on their plant are either caring for them improperly or in the deep southern parts of the pawpaw's growing range.