```r
library(lmtest)
```

```
## Loading required package: zoo
```

```
## 
## Attaching package: 'zoo'
```

```
## The following objects are masked from 'package:base':
## 
##     as.Date, as.Date.numeric
```

```r
dwtest(growth~tannin)
```

```
## 
## 	Durbin-Watson test
## 
## data:  growth ~ tannin
## DW = 2.0168, p-value = 0.3679
## alternative hypothesis: true autocorrelation is greater than 0
```