求翻译：银胶菊是一种半干旱植物，其物理机械性能与天然胶相似，且不含蛋白质。在天然胶供不应求，价格持续高涨的局面下，银菊胶现已成为美国等国代替天然胶的首选材料。是什么意思？

Guayule is a semi-arid plant, its physical and mechanical properties similar to natural rubber, and does not contain protein. Natural rubber in short supply, the price situation continues to climb, guayule rubber has now become the material of choice for the United States and other countries instead