The Land-Rover pauses at the top of Tullochgrue so that we can look out over the spectacular Rothiemurchus estate, which stretches from the Cairngorm Mountains to the banks of the River Spey near the tourist centre of Aviemore.

“The wildlife here, the flora and the fauna, never fail to get the kids going,” says senior ranger Scott Henderson.

The estate, made famous for its beauty in Elizabeth Grant’s Memoirs of a Highland Lady in the 19th century, has been in the hands of the Grant family since the 16th century.

“No matter what age or gender and no matter what country they come from, they will always remember Rothiemurchus because it’s unique,” says Mr Henderson.

Standing at Tullochgrue once, watching the pine pollen blowing out of the trees, some children asked if the forest was on fire.

Mr Henderson’s pride in the educational work undertaken by the ranger service at the estate is as palpable as the pleasure he takes from the panoramic view. “Whether it’s feeding our herd of red deer, our Highland cattle or the rainbow trout on the fish farm, we provide experiences most pupils will never forget,” he says.

“It’s all about enthusing the pupils and that’s not difficult when they catch sight of a pinemartin, a red squirrel, a capercaillie, a crossbill or an osprey.”

“Over half of Rothiemurchus is part of the Cairngorm National Nature Reserve which has some of Scotland’s - and Europe’s - finest wildland landscapes and wildlife,” says part-time ranger (and qualified physical education teacher) Ali Trinder. “Most of the estate has been designated as Sites of Special Scientific Interest.

“There is only 1 per cent of the ancient Caledonian pine forest left and we have most of that. We are allowing it to regenerate naturally.”

A short walk reveals the variety of species in the ancient woodland, with natives such as Scots pine, dwarf willow, juniper, alder, rowan (mountain ash), aspen and silver birch. Underfoot, among the bracken and blaeberries, we come across a rare orchid called Creeping Ladies’ Tresses. The estate boasts more than 400 orchid species, six of which are found only in Britain.

Rothiemurchus has more than 300 wild red deer plus herds of wild roe deer. But this is a working estate, so from them it has bred a herd of 18 red stags and 69 hinds with 31 calves, which are farmed commercially for their venison. The farm, which produces its own silage feed and grows barley for the whisky industry, also keeps a 55-strong crossbred herd of Aberdeen Angus, shorthorn, Simmental and Limousin cattle and about 60 Highland cows and two bulls.

“We have black and red Highland cattle. The red ae the most popular with the pupils, as they were with Queen Victoria,” says Mr Henderson. “It’s not uncommon for primary pupils to ask if they eat the pheasants!

“I came across a group of adults the other day standing in a field, petrified of the Highland cows! I had to guide them through.”

Dealing with the general public is a large part of the rangers’ job during the summer months. Apart from the fish farm - which produces about 100 tonnes of rainbow trout a year - the estate offers bank and boat fishing as well as clay pigeon shooting, off-road driving, cycling and mountain biking, pathfinding, hill walking, bird watching and camping.

But the educational aspect of their work is clearly one that the rangers relish. “Education is an essential part of our work. The general ethos is very schools friendly,” says Ms Trinder.

Feedback forms and questionnaires mean that the rangers are adapting and refining their educational work all the time.

“That goes for training as well,” says Mr Henderson. “We receive at least three weeks’ training every year from Scottish Natural Heritage on the flora and fauna, on protecting the listed wild flowers, the osprey nests and so on. But in a job like this, really you’re training all the time anyway.”

Conservation is a major concern to the estate, where once bears, lynx and wolves kept the red deer numbers in check. Although there is talk of reintroducing European beavers in areas near the estate, the rangers remain wary of the idea of reintroducing wolves.

“Some people say they’d help keep the deer numbers in check but I think they’d be more likely to feed off the bins, as urban foxes do,” says Mr Henderson.

“We had wild pigs - Iron Age pigs - for a while. But they kept breaking out of their enclosures. Then they began swimming over the Spey to root around in neighbouring estates, so they had to go.”

Health and safety is another important aspect of the rangers’ job. Children who feed the fish, cattle or deer are continually reminded to wash their hands before they eat - or suck a thumb, in the case of one primary pupil. “The herd is clean,” says Mr Henderson, “but ground rules remain. It’s a question of good practice.”

The best time for school parties to feed the trout, Mr Henderson confides, is in early summer because at that time of the year the ospreys are often seen.

“On a May or June morning you can see up to 10 ospreys feeding. We allow them to do it. We may lose some fish but it doesn’t affect the business in any real way.

“It’s great to watch the ospreys and to watch the pupils watching them. You can have a group of 30 pupils mesmerised as the ospreys are diving only 20 metres from them. They’ll never forget that, most of them. It’s just unique.”