So we searched the net and Google came up with the answer, by which time, there was further evidence in the form of large red beetles, grubs, and you could actually hear sounds of activity in the tree base, in the from of scratching and rustling - UGGGGGHHHH!
So we suspect the Red Palm Weevil, which is bad news, - the tree will most probably die. Various Govornments have adopted measures in an attemp to stop wholesale destruction of palm trees - and we are off to the garden centres for further advice, - We are questioning also whether this condition is reportable, as many accounts reccommend pouring parrafin into the crown - which I guess is worth doing anyway if you are going to loose the tree.
The red palm weevil (Rhynchophorus ferrugineus) is a curculionids beetle, a native of Southeast Asia. Since the early 80s and in some 10 years, it has invaded much of the palm trees on the Arabian peninsula, where there are numerous date palms, Phoenix Dactilifera. The jump to Europe has come with the massive importation of palm trees from Egypt; it was found for the first time in the province of Malaga in 1994. The Spanish authorities have intervened to try to eliminate the parasite, but apparently with little success.
The adult red beetles are reddish, 2.5 to 3 cm long. The female may deposit 200 to 350 eggs around cracks in the trunk or at the base of the leaves by digging tunnels within. Cuts in the branches result in a sap, which attracts the female; as a result it is best to prune only in winter.
Once the larvae are born, they will begin to burrow into the soft heart of the palm tree, and each one will burrow about a one meter long tunnel. All these tunnels will reduce the amount of water the tree can take up, resulting in the palm tree eventually dieing. The adult Red Weevils grow to be about 3-5 centimeters long. If the Red Weevil is discovered before the leaves of a palm tree begin to wilt through lack of water due to an infestation, then the tree could be saved, and if you put you ear to an infested tree, you should be able to hear the red weevil larvae, tunneling.
The red beetle attack in general is followed by the death of the tree, as by three generations they reach the inside of the palm. A small proportion of adult beetles will leave the tree to find other trees to colonize; but the vast majority stay put until the tree is destroyed and completely dead.
To date, there is no way of detecting the parasite early, which presents a serious obstacle to the adoption of measures to fight the beetles and prevent the full grown palm trees from being infected; So preventive treatments are recommended to stop this dangerous beetle attacking in the first place.
In fact there are not two insecticides, but three, but one of them is 45% Phosmet and authorized only for professional use in palm nurseries and should not be applied in either private or public gardens because of its high toxicity.
Of the two authorized insecticides, one is a chemical, imidacloprid and the other biological, namely Nematodes Entomopatógenos.
The time of treatment is directly related to the insect's activity. In the coldest months (December, January and February) there are virtually no flights of adult and more treatments can be applied. The insect begins its activity in March-April and the population is at its highest between June and November.