You are here. Cross U.S. Borders. Almost a million times each day, U.S. Customs and Border Patrol (CBP) officers welcome international travelers into the U.S. In screening both foreign visitors and returning U.S. citizens, CBP uses a variety of techniques to assure that global tourism remains safe and strong.
Reaching heights between 40 and 70 feet, the river birch is one of the hardier birch trees. They grow best in full to partial shade and thrive in well-drained, slightly acidic soils. The river birch is not a drought tolerant tree, preferring sites that are wet.aper Birch (Betula papyrifera). Paper birch trees are large, oval in shape and may be single or multi-trunked. They reach heights between 50 and 70 feet. Younger trees have brown bark, as trees age the bark turns white and peels to reveal an inner bark that is orange in color.
Living only about 30 years, it is a common pioneer species on abandoned fields and burned areas. Characteristics: Gray birch grows quickly to 20 to 30 feet tall and 15 inch trunk diameter, with an irregular open crown of slender branches. The tree often has multiple trunks branching off of an old stump.ray Birch has been commonly planted as a landscaping tree in southern Pennsylvania and New Jersey as it tolerates heat and humidity better than Paper Birch and is more resistant to Bronze Birch Borer and leaf miners.