```r
cor.test(growth,tannin)
```

```
## 
## 	Pearson's product-moment correlation
## 
## data:  growth and tannin
## t = -5.5654, df = 7, p-value = 0.0008461
## alternative hypothesis: true correlation is not equal to 0
## 95 percent confidence interval:
##  -0.9796643 -0.5972422
## sample estimates:
##        cor 
## -0.9031408
```