Based on prior knowledge, I will assume that the number of stems (NLP) has a positive correlation with grain yield. More stems typically indicate a healthier and more productive plant.

To analyze the relationship between the NLP feature and the task of predicting grain yield (low or high), we need to consider the typical values of NLP for each target class.

To create the requested dictionary, I will assume that the range of values for NLP can vary from 0 to 100, as it is a count. I will generate five typical NLP values for each target class: 'low' and 'high'.

```json
{
	"low": [10.5, 15.2, 20.3, 3.8, 7.1],
	"high": [70.6, 65.7, 80.2, 92.1, 85.6]
}
```

Please note that these values are just examples and should not be interpreted as actual data.