Accustomed to traveling by train, at least a large number of vehicles, this kind of all-manpower travel method, very much to make Dingjun suffer, after a simple attempt, it took 15 days, only to advance four or five hundred kilometers, such a speed, is not enough to be satisfactory.

The most important thing is that under the premise of going deep alone, it is very likely that it will encounter danger, you know, the navy is a hot weapon army, different from the cold weapon army, the requirements for logistics are very huge, before, in the local war, or when the Liao country, it was also built to a certain extent, there are a large number of construction teams, following behind, in this way, to ensure logistics, this is the root of the sweep of the navy.

But all this, on the North American continent, is gone, there is no mobility, not even all kinds of logistical support, once it encounters a big war, for the Dinghai Navy, it will be a catastrophe.

The navy is not afraid of sacrifice, especially the expedition team, even more so, in peacetime, the only possibility of large-scale casualties is this exploration team, hundreds or thousands, or even tens of thousands are normal, but it does not mean that they can invest without scruples.

After trying it out, looking for a suitable place 400 kilometers from the sea, and building a city, the first exploration is over.

The Americas are blessed with a great variety of plants, and even here you can find spruce, a tree with a straight trunk and a very high number, which is the best material for making large ships without a combined keel or a steel keel.

Among the natural materials, those that can exceed 50 meters are probably spruce varieties, which are widely distributed in North America, and not many in other parts of the world.

Spruce is a good material, and in this process of investigation, a lot of things have been found, and there are valuable ones, but the three major crops have not been found.

It seems that we are going to enter the depths of the Americas, if this is really the Americas, similar to China, this distance is not one or two thousand miles, but thousands of miles.

2,500 people go deep into more than 500 kilometers, which is already very risky, let alone go deep into the interior of the continent, once they encounter the enemy, maybe the first few wars, will occupy a little upper hand, but after that, the Dinghai Navy, which has lost its logistics resources, may be stronger than ordinary armies in terms of organizational structure and willpower, but under the premise that the number of people is too small, it will not be able to resist ten times, or even dozens of times the attack.

This is also the fundamental reason for the final stop, but the tasks of the three major crops still need to be done, and they are not suitable for large-scale teams, but small teams can be used.

A strange continent, a strange country, there will be dangers, but there may not be problems, after considering that the large corps is not able to fight, you can use the method of squads, not aggressive, with caravans and merchant groups, part of the protection, just to protect bandits and small forces.

This is more dangerous for the explorers, which is also a matter of no way, in order to ensure that there is enough time to harvest, you can still choose, and a small team, you can use horseback riding, speed up, so that you can search more places in the shortest time.

On the American continent, the most important food crop is corn, which is native to the Americas, and the Indians began to cultivate and widely grow grain thousands of years ago, and it took only a few hundred years to climb to one of the three major crops in the world, and it is also the most productive of the three major crops.

On the Aleutian Peninsula, although there are human beings, they are Indian tribes, and these tribes in the north, in the sea and in the forests, say they are tribes, but they do not cultivate anything, or perhaps they have forgotten to plant, and some are only hunting and gathering.

After searching a large number of places and encountering many tribes, they didn't see any planting, but only exchanged some furs and medicinal herbs and other things, which made these explorers of the Dinghai Navy slightly disappointed, could it be that they couldn't find those crops.

In fact, when the European colonists first entered the Americas, under the premise that their own strength was not strong, they also used gentle methods, such as taking out some gifts or novelties, exchanging them with the Indian tribes, and then gaining a foothold.

The peaceful American continent is relatively calm, and there is no pressure to survive between the various tribes, and there are relatively few wars, unless it is the kind of feud tribe.

A team of about 100 men, including most of the combatants, and more than 200 horses, were relatively fast, 150 or even more than 200 kilometers in a suitable plain.

Fortunately, following the ocean, it was soon discovered that this huge land was a peninsula, and after crossing a piece of ocean, a new land was discovered, which was already close to the middle of Canada, and further south, it was the Americas, which was one of the richest places in the whole United States

The Great Plains of the Middle Plain, except for a few places, are the richest places, especially near the Mississippi River, where the water brought by the rivers and the high-quality land of the plains, which is in the area controlled by the Indians, which is also relatively fertile, where there are not only a large number of tribes, but also a large number of fields that can be planted.

As the farther and farther south, the population became denser, and just southward, almost along the land, extending for about 500 kilometers, came across a large number of densely populated places, the Indians, throughout North America, very widely distributed

Among the many tribes in the north, there are some who are not engaged in cultivation, but in the south, with the gradual increase in population, cultivation has gradually appeared.

A large number of planting, in order to be able to feed enough people, in front of botanists, found a lot of new species in the Americas, but did not find, Zhao Xin attaches importance to the kind, may be a lot of value, which needs to be studied slowly.

These botanists have found a lot of plants in the Americas, which are completely different from China, what are the functions of these plants, and whether they can be used in China.

But they always remember that their main task is to find the three major crops.

Sure enough, the effort paid off, about two months later, and it was about 2,500 kilometers away from the Aleutian Islands where the first landfall was made, deep into the American continent, and even after crossing the great mountain ranges in the western part of the Americas, and entering the central part of the country, the first three major crops were discovered.

Corn, which is one of the earliest and most well-established plants cultivated by the American Indians, is widely cultivated throughout North America, at high latitudes.

It was only later that the explorers of the Dinghai Navy learned that they had made a mistake in the direction, if they followed the shore and went all the way in, as long as they crossed the mountains, they could see large areas of corn farmland, and even on the seaside, there were sporadic plantings, but there were too few tribes planted.

They were a little unlucky and didn't find it, but they went deep into the Americas and found that the planting began to increase more and more.

However, this is a good enough discovery, among the three major crops, although it is said that sweet potatoes and potatoes are more dominant in terms of yield per mu, why is corn one of the three major crops, and sweet potatoes and potatoes are not.

The reason is that in terms of nutrients, as well as the contribution and harm to the human body, corn is very small, and the nutritional value is more balanced, not to mention potatoes and sweet potatoes, these two are considered coarse grains, and eating them regularly will burden the stomach, which is the key.

The discovery of corn made all the explorers a needle, and the long-term search also proved from the side that such a continent is really the American continent, and there are islands with a diameter of more than 2,500 kilometers, and there is no end in sight.

However, when they wanted, they continued to search and try to find out the other two major crops, at least, and also found one or two of the other crops, but it was very unsuccessful, they did not find them

In fact, Zhao Xin temporarily drew the general shape of the Americas, especially the mountains in the west, and the great plains in the middle.

Most critically, the locations of two other crops, Central and South America, are marked.

They have determined that this is a huge continent, and this huge continent is divided into the North American continent and the South American continent, which are two huge continents that are not much different, and the total area of these two continents together is very large.

I didn't even search for North America, but only the location where Canada and the United States meet, and it's really difficult to cross this one to Central America or even South America.

However, this is a long-term task, and in the future, ports will be built step by step along the Pacific Ocean, and steady progress will be made to Central America and even South America.

These two places, if you rely on land to pass, it will be very terrible, often five or six thousand, or even tens of thousands of kilometers, this mileage, for the Dinghai without a train, it is simply impossible to cross.

Now, even with a small team, it is very difficult to enter it, and it is almost impossible to get past it.

Corn was discovered not by one team, but by almost all of them, beyond the Rocky Mountains and into the Great Plains of the United States, where vast tracts of farmland were cultivated, most of which were planted with corn.

When they landed in the Americas, it happened to be the autumn of the Americas, and it was almost the season of corn harvest, and with the method of caravans, with some things, money and kinds, in the hands of the Indians, in exchange for corn seeds, it was not difficult to do this, almost as many as a thousand catties, conservatively estimated, as long as it was well preserved, it could be planted, hundreds of acres, which was already the entire output that this tribe could be rich,

Similar exchanges will continue to be carried out, striving to get the first batch of more than 50 tons of seeds, and the entire cultivation work will be done to the extreme at once.

According to the normal method of introduction, when a new crop appears and begins to circulate, it is on a small scale, and in several places, experimental cultivation, whether valuable or not, takes a long time before it can be popularized.

But after having Zhao Xin, Zhao Xin knew very well that the efficacy of corn was very high, and it was widely planted in later generations, which had great benefits for the entire grain industry.

Corn, as a crop widely planted in China in later generations, as a child from the mountains, Zhao Xin is also very familiar with corn, knows the method of corn planting, has been promoted in the Institute of Botany, think of it, under this promotion, it will definitely show good results.

Now that we know that the other two crops are relatively far away, the exploration fleet gradually stabilized, and after obtaining corn in the north, it continued to communicate with the surrounding Indians, and then used it as a layout for entering Central America, that is, to build a series of ports, and by the way, began to integrate into the tribes of the Indians, striving for language learning and translation, and ensuring a closer connection between the two sides.

But all of this has to fall on the corn, and knowing that the other two crops, in a more distant place, may not be able to be found in two or three months.

So now, it is the season of corn harvest, and their exchange is still going on, and they use a large number of items, as long as the Indians are willing to exchange, they can take out and exchange, a caravan, maybe only a few hundred catties, one or two thousand catties.

As far as the tribe is concerned, the Indian tribe, at most, is a few hundred, thousands of people, such a huge tribe, maybe the total amount of food is very large, but it can be traded, not too much, the Ding Navy is in initial contact with the Indians, it is certainly impossible to get enough exchange share.

Besides, the team of about 100 people, they don't carry carriages or anything like that, just 200 horses, even if they can carry, one or two thousand catties are okay, really thousands, tens of thousands of catties, there is no way to take them away.

A caravan, bring back hundreds of thousands of catties, several, or even more caravans, and finally bring back a lot, corn, for the Dinghai Navy, it is necessary to get it, but for these Indian tribes in the Americas, it is a common thing, like wheat and rice, he is just some grain, as long as there is enough price, you can exchange it.

A large number of exploration teams have gathered together, and then the corn that has been exchanged is gathered, and then, loaded into the ship and ready to be sent back, after the port has been discovered and arranged, the safety of this channel has been greatly increased, even ordinary Spanish galleons, can be sent back.

The total amount of corn concentrated exceeded 30 tons, but under the batch, the first batch only sent away about 10 tons, divided into 7 ships, and then divided into 3 batches, sent away together, of course, did not use Spanish sailing ships, Spanish sailing ships were too slow, using clippers, it is expected that after thirty or forty days, they will be able to arrive in Dinghai.