Gajar ghas — a health hazardous weed
U.S. Walia and L.S. Brar
PARTHENIUM hysterophorus known as carrot grass (gajar ghas) is the most noxious weed of non-crop land area of Punjab. It has invaded the entire area which is considered to be no man’s land in the state. It is a tall growing, deep-rooted, much branched with 3 to 4 feet height at the fully flowered stage.

Asia’s useful trees and plants
K.L. Noatay
CHAMP is a tall handsome evergreen tree. Quite common in mixed temperate forests from Myanmar eastwards in Assam, Bengal, Nepal, etc. it comes up naturally along the foothills having an altitude varying from 500 to 1000 metres above mean sea level. It is also found growing in Western Ghats from Kanara to Kerala and some cool and humid valleys in Bihar.

FARM OPERATIONS FOR OCTOBER

Gajar ghas — a health hazardous weed
U.S. Walia and L.S. Brar

PARTHENIUM hysterophorus known as carrot grass (gajar ghas) is the most noxious weed of non-crop land area of Punjab. It has invaded the entire area which is considered to be no man’s land in the state. It is a tall growing, deep-rooted, much branched with 3 to 4 feet height at the fully flowered stage. Its highly incised leaves resemble very much to that of carrot plants. It bears terminal numerous flowers — white in colour. Flowers bear numerous seed, which are easily dispersed by wind or water. As soon as the winter season is over i.e. in the end of February, this weed starts appearing in flushes and continues to appear till October-November. This weed appears in four to five flushes or even more depending upon the rainfall pattern of the year in one year. However, during the rainy season i.e. July and August, nuisance value of parthenium is at the top.

Requirement for growth: Parthenium has very low water requirement and once it germinates either with rain or stored soil moisture, it can complete its life cycle with limited soil moisture. During the winter season, it does not disappear and remains in the dormant condition in busy (rossette) appearance, particularly under shade. The seeds are very light (fluffy) in weight and can be easily disseminated with wind or water from one place to another place. The seed germinates as soon as favourable moisture and temperature conditions are available.

Habitat: Due to a high rate of seed production, it has covered the entire state. It is a weed of mainly uncultivated lands, unbuilt or developing residential colonies around the towns, railway tracks, roads, drainage and irrigation canals, etc. This weed is also spreading in established gardens, plantations and recently its infestation was also noticed in some crops like sugarcane, cotton, fodders, vegetable crops, etc. This weed is very sensitive to water stagnation and does not grow in flooded conditions. There is very likelihood that in the near future, it may become a problem weed of some field crops, if no control measures are undertaken.

Health hazard: Parthenium hysterophorus (gajar ghas) has emerged as a great health hazard to human beings and livestock. It is a native of Central America, South America and West Indies. In Punjab, the infestation of this weed was noticed for the first time in Model Town, Khanna, in 1976. The weed has been reported to be a great health hazard, particularly for farm labour. Frequent contact with the weed causes allergy, dermatitis, eczema, asthema, pollentonsis and gangrene, etc. Even dried plant material such as trichomes on the leaves and stem are air-borne and dust may induce dermatitis in sensitive persons who do not have direct exposure to the plants. The symptoms of its ill effects start with itching and eruptions on eyelids, neck, face front, elbows and back of the knees. Some individuals are highly allergic to parthenium and they need admission to hospital during its peak growing season. It has been reported that semiclad individuals are more prone to the ill effects of parthenium, whereas children before puberty are spared.

It can also prove harmful and even fatal to milch cattle grazing in the infested area. The toxin ‘parthenin’ was detected in the milk of cattle grazing in areas with parthenium. It has also been noticed that parthenium is also responsible for the development of a bitter taste in milk if cattle are fed on grass mixed with this weed.

However, the incidence of disease may be directly proportional to the period of exposure to the weed or the extent and duration of the infestation of this weed. It has also been observed that persons suffering from the ill effects can be cured temporarily if moved to a weed-free area.

Awareness of the problem: To have effective control of this weed it is of utmost importance that the people are made aware of this weed, particularly its harmful effects and its growth behaviour. This will help in promoting the community or public participation to eradicate this weed.

Mechanical control: In situations where ploughing is possible i.e. in gardens, tree plantations, roadsides, open wasteland, etc. the weed should be ploughed under before the setting of flowers. Repeated mowing in playgrounds, lawns and levelled wastelands also provide good control of parthenium. If mowing is not properly done the stumps sprout again and produce profuse growth. Hence, care should be taken that the mower be operated at the ground level.

Where ploughing/mowing is not possible, uprooting of this weed before flowering can also provide much relief. The workers engaged on this operation should avoid physical contact with the weed plants and should preferably wear rubber gloves. Manual removal is an effective method but the persons engaged for uprooting should not be allergic to parthenium. Alternatively, the plants should be cut with some sharp hand tool with a long handle well below the ground level by avoiding contact with the plant. The cut plants should be stacked at one place and burnt.

This operation should be adopted on a campaign basis. It has also been observed that burning of plants in the highly infested areas during the October or early November, when the plants mature and become dry, can also help in controlling this weed to a large extent as this method helps in reducing seed bank of parthenium.

Chemical control: After testing a number of herebicides against parthenium, application of Atrataf (50 per cent atrazine) at the rate of 1 kg/acre or Round Up/Glycil (glyphosate) @ 1.01/acre have been recommended which provide very effective control of this weed. Anyone of the herbicides must be dissolved in 200 litres of water and sprayed uniformly over the area infested with this weed. Glyphosate is non-residual herbicide so any ornamental, vegetable, fruit or other economical plants can be sown when weed plants dry up. However, residues of atrazine remain for a long time in the soil.

For attaining good control, its application is very important. These herbicides must be sprayed when weed plants are very young i.e. when leaves are tender and it has not flowered. On grown-up plants, the dose of Atrataf should be increased from 1 to 1.5 kg/acre.

Precautions:

— Parthenium plants should be sprayed when these are young i.e. before flowering.

— Spray on a calm day only.

— Avoid spray drift to nearby flower and vegetable plants.

— Use at least 200 litres of water per acre.

— On grown-up plants use 1.5 kg of Atrataf per acre

— Atrataf treatment may be given to infestation of parthenium which is not to close proximity to any field/vegetable crops/ornamental plants.

— Glyphosate herbicide has no residue in soil whereas atrazine persists for two to three months in soil depending upon environmental conditions.

Asia’s useful trees and plants
K.L. Noatay

CHAMP is a tall handsome evergreen tree. Quite common in mixed temperate forests from Myanmar eastwards in Assam, Bengal, Nepal, etc. it comes up naturally along the foothills having an altitude varying from 500 to 1000 metres above mean sea level. It is also found growing in Western Ghats from Kanara to Kerala and some cool and humid valleys in Bihar. The scientific name being Michelia champaca and family Magnoliaceae, it has different local names in different territories. These are oulia champ, tita sopa, shimbu, sempagam, champakam, saga, etc. The species comes up naturally in rich, deep, moist but well-drained soil, preferably sandy loam, in warm and humid climate.

Champ is not found coming up naturally at places east of Allahabad. However, artificially, it is cultivated all over India, especially in private holdings, bungalows, offices and religious premises, mainly because of the fragrant flowers it bears. And, grown as an ornamental plant, it is found doing reasonably well in the Dehra Dun valley, Saharanpur and some other adjoining places. Some trees likewise planted in private bungalows in and around Shimla are also doing reasonably well.

It is a fairly fast growing tree. It tends to develop a cylindrical straight bole with dark grey and smooth bark. When growing on a favourable soil in a suitable climactic zone, it attains a height of about 20 to 30 m. and a girth about 2 m to 3 m in nearly 70 to 80 years of age.

Champ generally tends to develop a beautiful umbrella-like crown. The foliage is dark green, shining above and glabrous beneath. The leaves are simple, entire, ovate or ovate oblong measuring about 10 to 20 cm in length and 5 to 10 cm in width. New leaves appear during March-April.

The tree bears beautiful, large and whitish to light yellow flowers. These start appearing in April-May, emitting a lot of fragrance. The pleasant scent can be felt from quite a distance from the tree.

The fruit of champaca appear in May-June and ripen in August-September. The species produces enough sheed for natural regeneration in usual habitat, though a bumper seed year occurs nearly once in three years.

In matter of regeneration, in its natural habitat champ starts giving seed at an early age of nearly six years. Young seedlings come up in good number under and around the mother tree. Good care helps the crop establish early and fully. for ornamental planting, the seedlings are raised in nursery beds.

Michelia wood has diffused pores. Structurally it is soft and even grained and has distinct annual growth rings — six to seven per inch of diameter. The sap wood is white, while the heat-wood is olive green. The timber obtained from a mature tree is soft and yet strong and very durable. Weighing nearly 20 kg per cubic foot, it is easy to work and plane and takes good polish. Accordingly, it is very good for furniture, plywood, tea chests, battery separators, pencils, carving, ship building and decorative wooden items like cabinets, cigarette cases, radio cabinets and for door and window panels in house construction. These days the going market rate of good sized champ timber is nearly Rs 1000 per cubic foot.

The champ foliage serves as fodder for cattle, especially during grass famine. The bark contains alkaloids and tannins and is chewed with betel. Some people use it as an adulterant with cinnamon. The flowers, fruit and roots are put to a variety of local medicinal use. A paste of its leaves in any edible oil serves as an excellent dressing against rheumatism, cephalalgia, vertigo, ophthalmic, gout and inflamed parts. The flowers and fruits are also used against snakebite. In fact, various parts champ have several applications in ayurveda and unani systems of healing human maladies.

Start transplanting cabbage, mild-season cauliflower and knol khol. Keep line and plat-to-plant spacing at 45x30 cm for cabbage and cauliflower and 30x20 cm for knol khol. Plant cauliflower on ridges and others on flat beds.

— Start sowing mid-season pea for green pods and the Mithi Phali variety from middle of October. Use varieties Pb-87, Pb-88 or Bonneville. Use 30 kg seed per acre. Drill seed in line at 30 cm apart.

— Wilt and stemfly are serious problem of field pea, hence avoid early sowing in badly infested area. Treat the seed for the control of wilt and stemfly with Bavistin @ 1 g in 15 ml of water for 1kg of seed. Apply 3 kg Thimet 10 G or 10 kg Furadan 3 G per acre in furrows at the time of sowing.

— Weeds can effectively be controlled with the use of Afalon 50 WP (Linuron) @ 500 g/acre or Stomp 30 EC @ litre/acre as preemergence application i.e. within two days of sowing. Use 150 to 200 litres of water for uniform spray and use flat fan/flood zet nozzle only for this purpose.

— Complete sowing of the autumn potato crop in the first fortnight of October, particularly for seed production purpose. Use healthy seed tubers.

— Sow potato after applying 20 tonnes of farmyard manure, 82 kg of urea, 155 kg of superphosphate, and 40 kg of muriate of potash per acre. Farmyard manure should be applied about 10 days before planting potato, whereas fertiliser should be applied at the time of sowing preferably by mixing with soil to avoid injury to tubers. Higher doses of nutrients can be applied if soil test shows low to very low status of these nutrients.

— For weed control, use Atrataf 50 WP/Atrazine @ 200 g/acre or Isoproturon 75WP @ 500 g/acre or Stomp 30 EC @ litre/acre or Sencor 70 WP (metribuzin) @ 200 g/acre as pre-emergence or spray Gramoxon @ 500-750 ml/acre upto 5 to 10 per cent emergence of the potato crop and complete germination of weeds. Do not use Atrataf in those fields where succeeding crop is to be cucurbit.

— For the control of late blight, use selected healthy tubers for sowing. Follow high ridge method to avoid tuber infection.

— Disinfect the seed tubers in 0.5 per cent solution of Agallol or 0.25 per cent Emisan/Aretan by dipping for 10 minutes to control black scarf and common scab. Avoid sowing of potato in fields with high incidence of common scab. Keep the soil wet at tuberisation to minimise the scab infection. Follow high ridge culture to avoid tuber infection. If there is a heavy shower in the second-third week of October, protect the crop immediately by spraying Indofil M-45 @ 500-700 g/acre. Potato should not be grown in common scab-infested fields.

— On 15 to 20 cm high beds, sow 4 kg seed either of Punjab Red Round or Punjab Naroya, Punjab Selection (red skinned) or Punjab-48 or PDW-1 (white skinned) variety to raise seedlings for transplanting in one acre. Keep the ratio of nursery bed and field area 1:20 (8 marlas:1 acre).

— Start sowing nursery of tomato. Use 200 to 250 g seed of the recommended varieties in one marla (25 m) bed area to grow seedlings for an acre. Sow TH-2312, TH-802, S-12, Punjab Tropic and Punjab NR-7 for local markets and kitchen gardens, Punjab Kesri for medium distance markets and Punjab Chhuhara for long-distance marketing and processing purpose. For planting in nematode infected fields, sow nursery of only the resistant variety Punjab NR-7 or hybrid TH-2312. New varieties like Punjab Upma and Castle Rock can also be planted.

— Apply 50 kg of urea, 155 kg of superphosphate per acre for radish, turnip and carrot. Carrot also requires 40 kg of muriate of potash per acre. Sow varieties Punjab Safed, L-1 and Sel 2.1, Sel 233 and No. 29 of radish, turnip and carrot using 4.2 and 4 kg seed per acre, respectively. Sowing on 45 cm ridges is better than in flat planting because of high yield, easy harvesting, better root shape and richness in nutrients.

Sow palak, methi, lettuce and Chinese cabbage by using 5 kg seed for direct sowing and 200 and 250 g for raising nursery respectively.

— Progressive Farming, PAU