```r
Site3<-Lshell[Site=="Site_3"]
t.test(Site1,Site3)
```

```
## 
## 	Welch Two Sample t-test
## 
## data:  Site1 and Site3
## t = -0.68235, df = 8.1748, p-value = 0.5139
## alternative hypothesis: true difference in means is not equal to 0
## 95 percent confidence interval:
##  -26.36357  14.28953
## sample estimates:
## mean of x mean of y 
##  100.7692  106.8063
```