152 Commercial Gardening 



and F. nodosus. Seaweed is variously known as wrack, bladderwrack, 

 black wrack, and black tang in different parts. During the summer 

 months, after the tide has receded, the seaweed is gathered and laid out to 

 dry along the shores. It is turned over a few times, as if it were hay, and 

 when sufficiently dry is stacked in conical heaps for autumn and winter 

 use. During the winter seaweed cannot be dried and stacked in this way, 

 as it melts away into an oily liquid. It is therefore applied direct to 

 the soil when collected at this season. The value of seaweed is due to the 

 amount of potash it contains from 30 to 40 Ib. in a ton. It also contains 

 about 10 Ib. of nitrogen and 10 Ib. of phosphoric acid, as well as 11 to 18 

 Ib. of lime to the ton. It is therefore a " complete " manure, but is not so 

 valuable as farmyard manure. For Potatoes, Peas, and Beans it is excel- 

 lent in light soils, and a good dressing would be from 12 to 20 tons per 

 acre. 



Soot. This is principally composed of carbon, and is not only valuable 

 as a manure, but also as a preventive against attacks of slugs, snails, cater- 

 pillars, &c. One ton of soot contains about 90 Ib. nitrogen, 25 Ib. phosphates, 

 25 Ib. potash, and 200 Ib. carbonate of lime. It is therefore an excellent 

 all-round manure, and after it has been exposed to the air for six or eight 

 weeks may be safely used for almost any vegetable or flower crop in the 

 open air. From 30 to 50 bus. per acre is a fair dressing. Soot is highly 

 valued as the basis of a liquid manure by gardeners who grow large num- 

 bers of plants in pots. About 1 pk. to 30 gal. of water will yield a useful 

 liquid manure. It is better to put the soot into a bag and sink it in a tub 

 of water, as the loose soot does not mix freely with the water. Owing to 

 its chemical composition it is a much better and safer liquid manure than 

 sulphate of ammonia or nitrate of soda. 



Blood Manures. Blood may be regarded as a complete fertilizer, as it 

 contains not only nitrogen (from 2J to 5 per cent in a fresh state, and from 

 6 to 14 per cent in a dried state) but is also rich in all other plant foods, as 

 may be seen by the following analysis of the ash: 



Per cent. 



Sodium phosphate ... ... ... ... 16'77 



Calcium and magnesium phosphates ... ... 4-19 



Oxide and phosphate of iron ... ... ... 8 '28 



Sodium chloride (common salt) ... ... 59 '34 



Potassium chloride ... ... ... ... 6'12 



Calcium chloride ... ... ... ... 3 '85 



Calcium sulphate (gypsum) ... ... ... 1*45 



TOCHJQ 



[t will be observed that common salt constitutes more than half the weight 

 of blood ash. When fresh blood can be obtained from slaughter houses it 

 is best mixed with large quantities of soil and then allowed to " mature " in 

 a heap until wanted for use. Dried blood is a more concentrated source 

 of nitrogen than fresh blood, as water has been eliminated. It is a good 



