Nathan Radley fills the Knothole with cement because he knows that Aurthur is the one giving Jem and socut the gifts, and he uses this as a way to prevent it. As an exuse, he tells the children that the tree was sick.
Nathan Radley fills the hole in the tree where gifts are placed with cement to stop Boo Radley from communicating with Scout and Jem.
Nathan Radley puts cement in the knot hole to stop Boo Radley from leaving gifts for Jem and Scout. He believes that Boo's interactions with the children are inappropriate and wants to cut off their communication.
Nathan Radley tells Jem and Scout that he filled the knot-hole with cement because the tree was dying and he didn't want it to fall on someone. However, it is later revealed that he filled it to prevent gifts being left for the children by Boo Radley.
He said the tree was old and it was dying and that people fill trees with cement when they're sick.
Nathan Radley fills the hole in the tree where gifts are placed with cement to keep Boo from communicating with the children.
There would be no more surprises in the Radley tree because Nathan Radley filled the hole in the tree with cement to prevent Boo Radley from communicating with the outside world. This action was likely done to isolate Boo and prevent him from interacting with others.
Jem and Scout discovered that someone had filled the knot hole with cement, sealing off the opening where gifts had previously been left for them by Boo Radley. This action by Nathan Radley signified the end of their secret communication with Boo.
Nathan Radley claims he is filling the knot hole in the tree with cement to protect the children from any future presents being left for them. However, his true motive may be to prevent Boo Radley from communicating with Scout and Jem.
The cemented hole in the tree represents Boo Radley's isolation from society. Nathan Radley fills the hole with cement to prevent Boo from communicating with Jem and Scout. Jem is heartbroken because he realizes the cruelty of this action.
Nathan Radley fills the tree hole with cement because Jem and Scout had been leaving items inside of it for Boo. Boo was taking the items and replacing them with his own home made items. Nathan Radley wanted to end the communication between Boo and the Finch siblings.
Nathan Radley seals the knot-hole in the tree in front of the Radley place because he believes it is a bad influence on Boo Radley and wants to cut off communication between Boo and the children. He fills the hole with cement to prevent gifts being left for Boo.
The children are prevented because Mr. Nathan Radley filled the hole in the oak tree up with cement.