188. Fourth International Congress of Rice Growers at Vercelli, Italy (1912): Control of Weeds in the Rice-Field. 189. The Blackberry- Bud Moth: a Promising Agent of Control.

GENERALITIES.

States.

a) GENERAL

190. Papers on Coccidae, or Scale Insects. The Genus Fiorinia in the United

-

MEANS OF PREVENTION AND CONTROL. 191. Parasites of Apple Weevil observed in the Valledi-Non (Trent, Austria). 192. Experiments in France in Acclimatizing some Species of Glandına which destroy other Gasteropods. 193. The Caterpillar Pest of the Mokameh "Tal" Lands.

b) SPECIAL

197. Spinach: Enemies.

INSECTS AND OTHER INVERTEBRATES INJURIOUS TO VARIOUS CROPS. 194. Cotton: Insect Pests in South Africa. 195. Sugar Beets: Conorrhynchus luigionii and Lixus junci in Campania, Italy. 196. Atriplex hortensis: Insect Pests. 198. Garden Crops: Elegant Grasshopper in South Africa. in Italy. 200. Willows: Rhabdophaga salici perda in Italy. chychiton): Tyora sterculiae.

199. Oak: Tortrix viridana

201. "Currajong" (Bra

NB. The Intelligence contained in the present Bulletin has been taken exclusively from the books, periodicals, bulletins, and other publications which have reached the Library of the International Institute of Agriculture in Rome during the months of December 1912 and January 1913.

The Bureau assumes no responsibility with regard to the opinions and the results of experiments outlined in the Bulletin.

The Editor's notes are marked (Ed.).

FIRST PART.

ORIGINAL ARTICLES

The Present Condition of Citrus Growing in Spain

by

JUAN M. PRIEGO

Professor of Horticulture in the Madrid Higher Institute of Agriculture.

According to the latest official figures, which are fairly accurate, there are in Spain 117 459 acres under oranges and 6363 acres under lemons. Other citrus fruits are not grown to any extent, and probably 2500 acres would cover the area under limes and citrons; further, these are hardly ever grown alone, but are planted in small numbers among oranges and lemons.

The production of fruit in 1910 was 782 200 English tons of oranges and 623 250 tons of lemons.

THE CHIEF ORANGE-GROWING REGIONS OF SPAIN.

The principal orange-producing centres in Spain are the renowned adjoining provinces of Valencia and Castellôn, the province of Murcia and the province of Seville: these represent three distinct regions.

In the first region sweet oranges, particularly Valentian, Imperial, and Tangerines, are almost exclusively grown: these are in demand on the English market and for consumption in Madrid. There are many other varieties, in particular blood oranges, which are much in demand for Germany owing to their good keeping qualities.

Orange growing has long been carried on in this region along the coast and in the lower valleys of the rivers, where frosts are quite exceptional. It has now extended up the lower slopes and first plateaus of the neighbouring mountains, but the crop is here not quite certain. The soil in the orange groves on the low ground is clayey in Castellón and lighter in Valencia, but always deep; out of the valleys the cultivable soil is poor and can only support oranges when carefully improved. This region also includes the groves in the provinces of Tarragona and Alicante, which adjoin it on the north and south respectively. Most of the oranges

exported and consumed in the centre and north of Spain are grown in this region. Of the 120 000 acres in Spain, nearly 100 000 belong here, and of these some 850 000 are in the two provinces of Valencia and Castellón. The chief centres of production are Alcira and Carcagente in the wide valley of the Jucar, and Burriana and Villareal in the Mijares valley. The sub-region of the Balearic islands may be put with this region, but its production is declining and of little importance.

The density and even distribution of the population and the careful work of the men who attend to the trees and gather the crop are factors no less favourable than the climate to the good results of orangegrowing.

The principal orange-groves in the province of Murcia are about Murcia itself and in the lower valleys of the Segura and the Vinalopó. The meteorological conditions are much the same as in the first region. The soils of the Murcia and Segura valleys are mostly more siliceous, and are very well suited for lemons, largely grown in this region, and limes. These two crops, which cover nearly as large an area as the various varieties of oranges, give sweet and exquisite fruit, which does not keep very well.

The distance from the ports has been the chief reason why these crops have not developed as well as in the Valencia region.

The eastern provinces of Andalusia may be included in this second region, with which indeed they are already connected geographically. Almeria and Malaga each grow some 1750 or 2000 acres and Granada about half this area. The valley of the Almanzora and the maritime and central parts of Granada and Malaga are the only areas in which this cultivation leaves the coast and extends to the sheltered slopes of the sierra of the Alpujarra. The soils are formed of transported material and are very fertile owing to the weathering and transportation of the parent Silurian slates.

The commonest varieties are the Chinese orange, the Malta bloodorange, the Grano de oro and Tangerines; the fruit is sweet and of good quality. Bitter oranges are also grown in Malaga and limes in Granada and Almeria.

A good number of cases of oranges are exported to England from this region. The home market takes the lemons and limes at good prices. Near the limits of this zone, especially in Granada, orange growing is somewhat neglected, so that the trees often suffer from gummosis. As the dead trees are not replaced, the yield is diminishing; it was, however, never more than sufficient for local needs.

The third comparatively important region is that of Western Andalusia, whose centre is the province of Seville with over 3500 acres of groves. Here the climate is less favourable, owing to the cold winters which are general. The chief districts are Seville, Mairena, Carmona and Dos Hermanas. By the valley of the Guadalquivir this important region communicates with the sub-region of Cordova, where it reaches its northern limit on the sheltered slopes of the cordillera of the Morena.

With this region are also connected the groves in the provinces of Cadiz and Huelva, all on deep and fertile alluvium. The development attained by oranges in this region is generally greater than in Valencia. Bitter oranges do best, as their flowers can stand cold; on and near the coast limes do pretty well, and those from Conil are celebrated. Many other varieties, both red and yellow fleshed, grow in the gardens and groves beside the ones mentioned.

The cultivation is lucrative here, for the production is somewhat above the consumption and leaves room for export. The oranges picked in autumn are sent away, while those that hang all through the winter and get more or less damaged by frost are sold locally at prices up to IOS. per cwt. ($2.20 per 100 lbs.).

Lack of care, particularly as to manuring and pruning, has led to the trees becoming infested with all the diseases which have recently appeared.

In some of the remaining provinces, such as Barcelona in the northeast, Badajoz and Cáceres in the south-west and Pontevedra and Corunna in the north-west, oranges are grown on a small scale in sheltered places or close to the sea.

The cultivation of citrus trees is not everywhere equally careful. In this respect the east coast (Valencia) region may be taken as a model. The working of the ground is generally satisfactory, except that trenching is not usually carried out before starting a grove: this is due to lack of an economical implement for the purpose.

Manuring is copious, but the formulæ used are not always sound. Irrigation leaves nothing to be desired, as in this region it has long been practised.

In this region the picking begins in early November for Imperia's and Tangerines. Some fruits are picked first rather green to relieve the tree and encourage the ripening of the rest; a second picking is carried out in January and February, and the late fruits are picked dead ripe up to April. In the province of Valencia there is also a small second crop towards the end of summer the result of a late and more or less irregular second flowering.

In the Andalusian region the cultivation is much less careful: the manure is almost always insufficient, and the neglect of pruning is shown by the tangled crowns of the trees. For this reason the trees have suffered badly from diseases.

The list of pests which infest all our orange-groves with greater or less intensity is large; the following are the most important: Chrysomphalus dictyospermi Mask.(" piojo rojo "), Mytilaspis citricola Pack ("serpeta "), Dactylopius citri Risso ("cochinilla algodonosa "), and Aspidiotus hederae Vallot ("piojo "or "cochinilla blancos ").

The first of these is the most important, owing to its prevalence and the damage it does; the agricultural associations and Governement inspectors have organized a campaign against this scale: this campaign began to be effective as soon as hydrocyanic acid fumigation was taken

up and the worst attacked provinces were provided with the necessary staff and appliances for the work. The Committee of "ingenieros agronomos" to whom the work was entrusted has now 32 tents and an efficient staff of trained men.

ECONOMICS OF ORANGE GROWING.

The figures given above for the area and yield of citrus fruits in Spain, which show what great importance these crops now have for the country, have been reached in a short period, for in 1870 the production was only one-third of what it is at present.

The upward movement, which was due to the demand on the English market and the extraordinary development of sea-transport, kept on increasing in the last decades of last century. In the east coast region, particularly in Valencia and Castellón, the groves increased very rapidly. In Alcira, Játiba, Carcagente, Villareal, Almanzora, Burriana and many other districts they increased four- or five-fold in a few years. Very poor land was brought under cultivation at considerable expense for improvements, including drainage or irrigation. This great extension slowed down considerably towards the close of the century, owing partly to economic conditions becoming less and less favourable to this superabundant production.

The accompanying table gives the figures for exports for the decade 1901-1910.