A History of Chinese Americans in California:
Technology Brought From China
The presence of the ailanthus tree (the so-called “Tree of Heaven”) throughout California has long been a puzzle. The tree is native to China, but not to the United States; yet it grows profusely in those regions where early Chinese immigrants lived. All sorts of fanciful explanations are given — that the Chinese accidently brought the seeds to this country in the cuffs of their trousers (their trousers did not have cuffs), or that the Chinese brought the seeds to this country because they were homesick. The real reason Chinese immigrants brought ailanthus seeds to this country is that the trees are thought to contain an herbal remedy beneficial for arthritis.  The Chinese “wedding plant” was also brought to this country as an herbal remedy, but is less easily recognized.
Herbal medicine fulfilled an important health need in the nineteenth century for both Chinese and non-Chinese alike. Western medicine had not yet developed wonder drugs, anaesthetics, vaccinations, or sophisticated surgical techniques. Patent medicines were widely used, and their contents were not regulated by any agency of the government. Drastic measures, such as bleeding, were sometimes resorted to. On the other hand, Chinese herbal remedies had one to two thousand years of use be hind them. In fact, some so-called “wonder drugs” are actually synthesized forms of various herbs. Even today, some medically trained Chinese Americans prefer some herbs to their synthesized forms because the natural herbs have no side effects. [33,Interview with Dr. Herbert Yee (1978)]
One of the ancient building techniques brought from China was construction using rammed earth. While adobe and rammed earth are of ten associated with Spanish and Mexican cultures, rammed earth was a construction technique in use in China as early as 1500 B.C. This technique involves packing mud between wooden forms and hammering it until it becomes as hard as stone. It is an inexpensive building technique, but it is vulnerable to rains and dampness. When it is used in South China, where the weather is often damp, buildings are faced with stone for added protection.